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Watch SpaceX ACTUALLY hop Starship SN-5 150m!!!

Everyday Astronaut · Youtube · 530 HN points · 4 HN comments
HN Theater has aggregated all Hacker News stories and comments that mention Everyday Astronaut's video "Watch SpaceX ACTUALLY hop Starship SN-5 150m!!!".
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Gene and Rachel from Spadre [@SouthPadreIsle] are right at the edge of the exclusion zone with one of my my slow motion cameras to catch SpaceX perform a test flight of Starship SN-5!

Follow my friends @SpacePadreIsle for all their hard work and help! - https://twitter.com/SpacePadreIsle

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Aug 04, 2020 · 530 points, 383 comments · submitted by lpellis
zizee
No one has seemed to have mentioned it yet, but the game changer of Starship will be full reusability of both the first and second stage of the rocket. Falcon 9's reusability of the first stage was a huge step towards making access to space a lot cheaper. If SpaceX can realize full reusability with Starship it will enable things like large scale moon bases, space hotels and mars colonization. They still have a lot of challenges ahead of them, but today's hop takes us that much closer to the future of space as presented in films like 2001 A Space Odyssey.

The future is exciting!

llboston
Another significant thing is that Starship is designed to be mass manufactured at a relatively low cost. SpaceX can crank out thousands of Starships, fly them to Mars and build a million people colony. Starship is truly a game changer!
valuearb
This is a very key point.

The Falcon 9 isn’t cheap because of reuse (yet). It’s cheap because of mass manufacturing. The Rs-25 engine costs over $100m each, Ariansoace Vulcains around $20M, typical large rocket engines over $10M.

SoaceX Merlin costs about $200,000 each to make. The Raptor will be close to that. Thats why SpaceX can pursue the large number of redundant smaller engines design strategy so successfully.

Reuse has lowered Falcon 9 costs internally, and increased its private discounts, but not it’s public pricing. When the cost benefits of reuse finally cascade through public pricing and through the entire stack with Starship, you have a SuperHeavy launch system putting 150 tons in orbit even cheaper than a single Falcon 9 launch.

For comparison, the Shuttle was over $40,000 per pound to Orbit. The SLS will be around $10,000/lb to orbit if you don’t count developmental costs at least 3x that.

The Falcon 9 is $1,500/lb to orbit, and Falcon Heavy $1,100/lb to orbit. Starship will lift more payload to orbit than the SLS, and 4x as much as the Shuttle, for between $100 and $300 per pound.

mschuster91
> Reuse has lowered Falcon 9 costs internally, and increased its private discounts, but not it’s public pricing

It's not just a discount - it is the reversed equivalent of banks charging interest for a loan due to failure risk. Private customers getting discounts accept the increased risk that some re-used part fails. Essentially SpaceX has managed to have their r&d subsidized by paying customers instead of having to borrow money, launch dummy payloads and pay the money back.

jacquesm
You write that as if it is a done deal. Mars' atmosphere is roughly .5% of that of Earth and almost exclusively CO2. Temperature ranges are well out of what they are on Earth. It is hard for technology to survive there, it is impossible for people to survive there until there has been an unbelievable investment in infrastructure.

If you think there will be a million people colony on Mars in your lifetime than you are not in touch with the physics of this kind of endeavor. All of our GDP for the next 50 years pooled together would likely not be enough to pull off a feat like that. The scale we're talking about here is too large to even contemplate.

10 people in a shitty little dome, maybe. Right up to the moment they die because of some small mishap.

ben_w
Although I’m also not expecting 1 million people on Mars in my lifetime, I think you’re assuming SpaceX never gets close to the Musk price goals.

You might be right to do that — I’m no rocket scientist — but the target price would get a million people there for $200 billion, not your $5 quadrillion.

Yes, I also expect the first few thousand to be in easily damaged domes. I also expect them to bring some of The Boring Company equipment with them, as it is part-owned by SpaceX and the stated raison d'être of TBC being pointless in a future of fully self-driving cars.

nickik
How are tunnels pointless in a future of self driving cars, the opposite is true, tunnels make even more sense when cars drive themselves.
ben_w
Self driving cars done right will be able to do full speed while literally, not metaphorically, touching bumpers.

Traffic jams with human drivers happen spontaneously when the cars get close enough that overcompensation turns into a negative spiral.

nickik
So in the city of the future you gone have 1000s of self driving cars going full speed threw the city? It makes much more sense to open up the city for people and ban cars for the most part. Move the transportation under ground.
ben_w
Please, millions.

The roads are already there, electric cars are quiet, road trains are even more efficient.

I am no fan of American city design, having half encircled Davis CA on foot, having found the suddenly-terminating sidewalks in Salt Lake City, and having walked the really boring route from San Jose railway station to the hotel in the top left corner of the Apple Maps icon.

(NYC is surprisingly pedestrian friendly though).

nickik
In Europe we are already trying to make more space for pedestrians specially around the city center. The value of the land above ground is incredible. Freeing up those spaces from cars makes sense and is incredibly nice.
ben_w
I know, check my profile ;)

But:

1. Musk doesn’t live in Europe, he set up TBC while stuck in a traffic jam in Los Angeles.

2. Solid car trains moving at full speed (whatever that is for the road, 20 kph for residential or much higher than the current rules for highways) use less land area than any other traffic, so some lanes can become bicycle only or whatever.

3. They can “perfectly” obey traffic lights and give way to pedestrians

4. Raised walkways are cheaper than tunnels

bconnorwhite
The other factor is that Musk has nothing better to spend his money on. With Tesla + SpaceX + Boring + Neuralink he'll likely be a trillionaire by the time Mars colonization is full swing. Even if the price was $2T instead of $200B, Musk might be able to fund most of this himself.
ncmncm
To get a sense of the difficulty, imagine sending a million people to the South Pole to set up a self-sustaining colony. That would be much more than 1000 times easier than establishing such a base on Mars.
fastball
I'm interested in living on Mars. I'm not interested in living in Antarctica.
AtlasBarfed
Massive domes to act as greenhouses, melting a couple miles of ice cover. Fossils and untapped resources. Antarctica could be a lot of fun to colonize.
bconnorwhite
True, but I'm not sure difficulty is as relevant if the motivation is there. You can't terraform the South Pole. Mars reopens the frontier whereas the South Pole is a dead end
ncmncm
The South Pole starts out way more terraformed than Mars can ever be. It has air, water, gravity, and is warmer. You can just put up domes and it's already way better than Mars. Mineral wealth is only a mile down, under the ice.

Under the sea starts out way more terraformed than Mars can ever be. It has water, gravity, and is warmer. Mineral wealth is right at hand.

The cloud tops of Venus start out way more terraformed than Mars can ever be. It has air pressure, gravity, water, carbon, sulfur, and shirtsleeve temperature.

What motivation does Mars provide that those don't?

ben_w
If your goal is to be a multi-planet civilisation, neither Antarctica nor the oceans of Earth would work; also the layer of Venusian atmosphere that you’re describing is way too cold for there to be useful quantities of metals you could extract from the rain (unlike the lower layers, where mountain tops are frosted with metal: https://www.popularmechanics.com/space/deep-space/a11506/hea...).

The other option is the Moon, which has even less atmosphere and even bigger temperature swings than Mars.

ncmncm
Planets are for extreme primitives, anyway.

But the point was, if you haven't even proven you can settle a mildly challenging environment, your odds on an actually difficult one don't look good.

ben_w
We know by demonstrations that we can make settlements in Antarctica and underwater, we just don’t have any reason to do more than science and military.

Venus, you could only settle by bringing in everything from outside unless and until you can convert the atmosphere in a large way into building materials — Mars at least you only need to convert it into fuel, because you can do at least some of your construction from rocks.

ncmncm
All the settlements on Antarctica are utterly dependent on enormous support frequently airlifted from outside. There have been no settlements underwater at all; little more than camping trips have been essayed.

On Venus, plastics, carbon fiber, water, buoyancy gas, and breathing air (I repeat myself) can be made directly from the air and clouds. Plastic and carbon fiber gives you building materials. Robots can gather minerals from the surface and deliver them by balloon to the cloud tops. Insolation provides abundant power, moreso than here; or, a lightweight, unshielded nuke plant may be suspended a mile or more below industrial plant, supported on its own balloon.

Mars will be much more unpleasant than Antarctica. We don't even know whether people can live for long in Mars gravity. We know that long weightlessness is quite harmful.

ben_w
If you’re going to use that standard against nuclear submarines and deep-sea oil drilling, it is unreasonable to also say we can make those things from Venusian air. Yes, in a lab, sure — that’s proof of concept, far less than a camping trip, and roughly the same level as extraction of oxygen from rocks.
Jach
Easier is a downside.
ncmncm
It would be smart to demonstrate ability to do thing A before attempting thing B that is 1000 times harder.

With any luck, things you learn actually doing A, and then A' that is 10 times harder, and then A'' that is 100 times harder, will all turn out to be useful, even necessary, in tackling B. Failure is always an option, but there is no point in choosing it at the outset.

cookingrobot
Maybe SpaceX should practice colonizing in Antarctica. They could fly all their gear in on Starships and do a dress rehearsal.
shireboy
I’ve often said the same thing. South Pole and underwater cities would be easier than mars or even moon colony. As much as I want the later to happen- I think 1 million people on Mars or Moon will require something that makes them more appealing than even the worst Earth locations. That has to be something pretty drastic. Elon says motivation will be “it’d be cool”. I don’t think that is enough motivation. Still, I’d rather have the capability developed than not, and hopefully those motivations present themselves without being too dire (like a comet heading our way)
hugs
A science outpost, specifically as a place to put telescopes, seems the most compelling. The rest of the population would then grow along side the science outpost to service it (food, transportation, etc.) A looong time until a million people, though.
buzzwordninja
Why would you put a telescope in a gravity well though?

Would it not be easier to build large structures in orbit or at one of the Lagrange points?

ba2plus
There's been some really interesting ideas for a new generation of telescopes that Starship's cargo capacity could enable. Telescopes on the far side of the moon are the classic example. They'd be shielded from the sun for 14 days out of 28, permanently shielded from Earth, and still have all the advantages of being in a vacuum. Gravitational-wave telescopes on the geologically-stable lunar surface are another interesting idea.

But I think my favourite idea is infrared scopes in the polar craters, some of the coldest places in the solar system. You don't need a complicated JWST-style extendable sun shield or limited helium supply. You are limited in terms of direction, but that's not a bad tradeoff.

throwaway0a5e
Africa was in Europe's back yard yet when they got the opportunity they colonized the Americas. Colonizing a formerly unexplored place where nobody has yet laid claim has a lot of appeal (and this time we (probably) don't have to kill/displace the natives to do it).
None
None
pfdietz
Europeans were kept out of Africa by disease.
menybuvico
I always heard it was a logistic issue more than anything else? Getting from Europe to the Americas and then back in a sailing vessel is easier than getting to Africa's East coast and back.
pfdietz
Which explains why Africa was colonized so much more successfully than (checks notes) ... Australia?
mschuster91
I'd rather say the Europeans were kept out of Africa because of nowhere near European levels of valuable resources (think farmland, wood) other than slaves for centuries. Diamonds and uranium are a recent thing.
pjkundert
TBM FTW.
valuearb
I million people will be very hard.

But the first starship missions will drop 100 tons each to the surface of Mars at a cost of a few hundred million dollars each. And they will send dozens of Starships that first trip, building an camp with over a hundred explorers and scientists the first synod.

They will have thousands of tons of equipment and supplies, and their habitats will have multiple redundancies and be easily repaired.

Mars is far easier to survive on than the Moon, for example. The temperature ranges are far milder, Mars reaches 70 degrees Fahrenheit at its equator during the day. The day is the same length as ours. There is adequate solar for power, tons of water, and a plethora of other easily accessible resources from CO2 to Iron.

zamalek
> mass manufactured at a relatively low cost.

... which also explains Tesla, mass production of Earth-faring machines is one way to prepare for mass production of space-faring machines (and battery tech is going to be important for living in space). When you look at Musk's ventures, they really all end at Mars.

laichzeit0
The Boring company. Develop tech to drill deep tunnels on Mars? Electric cars and batteries cause you will need that on Mars? Even the Cybertruck looks like something destined for Mars.
ba2plus
And a Starlink network would mean an instant global Martian internet.
eric-hu
Can you recommend resources for reading more about the long term plans of Starship?
yreg
Not the parent poster, but there is

[0] Making Humans a Multiplanetary Species / Elon's original presentation from IAC 2016 - https://www.youtube.com/watch?v=H7Uyfqi_TE8

[1] Starship Update / 2019 - https://www.youtube.com/watch?v=sOpMrVnjYeY

themgt
Yep, and in addition to both of these, Starship is also designed:

* to be fueled / ignited such that it can be refueled in-situ on Mars & then launched back to Earth, without advanced rocket fuels or the TEA-TEB chemical igniter.

* to be able to refuel from another Starship in-orbit

The combination of all of this, if they pull it off, will be the ability to send truly massive payloads to Mars, faster and cheaper than anyone could have imagined just a few years ago.

To me it does really show the benefit of taking a systematic approach, working backwards from the goal "get to Mars and stay" in a resource-constrained environment. They've very strategically targeted the technology/engineering required to bring the costs down to something reasonable, while NASA's approach for 50 years has basically been versions of "can you give us one trillion dollars?" (or "we can put a couple humans on Mars for 3 days for $100 billion")

Today's Starship hop is getting very near the nail in the coffin for SLS. I still have some concerns about their crazy re-entry flip, but the speed SpaceX is moving is leaving everyone else in the dust.

m0zg
I wish I could invest into SpaceX. Such a slam-dunk rarely presents itself, and an opportunity to change the world for the better _while also making money_ is rarer still.
dodobirdlord
It seems you could buy a stake in a number of publicly traded companies and funds that themselves own a stake. Seems like Google and Fidelity each own about 4% of SpaceX, maybe Fidelity is offering it as a component of some fund?

https://en.wikipedia.org/wiki/SpaceX#Ownership,_funding_and_...

adventured
Google at least is a bad option. You won't actually get any value representation, any exposure, due to their extreme market cap.

Most likely close to 0% of the SpaceX ownership stake is represented in Google's stock. Let's assume though for the sake of argument that some large part is, say $1.3 billion of the stake is represented (3% of $44 billion). That's equal to about 1.3% of Google's market cap (~$1t).

Whatever you do never buy a stock on that kind of premise. Risking the other 98.7% of your capital to get a meaningless piece of something else (which is already a big something else at a $44b market cap). If SpaceX doubles in value, you'll never notice it (you put $1,473 into Google, SpaceX doubles, max scenario you might make $20). It may be one of the worst reasons to ever buy a giant like Google. People commonly make this mistake when buying Berkshire Hathaway or certain other conglomerates, thinking they're getting a 1-to-1 direct exposure to the Berkshire portfolio (among their equity holdings, only a few matter at all, as with the Apple holding at $110b). I often see it pitched as a form of bonus diversification. Cash and equity holdings on the balance sheets of public companies are essentially never represented at full value in the market cap. The larger the company and the smaller the asset in question, the more likely it is to have something more toward zero representation.

jbay808
Math check -- I think Google's SpaceX ownership stake would be closer to 0.13% of Google's value, not 1.3%. Is that what you meant?
dmurray
I don't get the Berkshire Hathaway analogy. If you buy that stock, in what way are you not getting "1-to-1 direct exposure to the Berkshire portfolio"? You're owning the same investments Warren Buffet owns, in the same proportions, to within a rounding error.

It would be a mistake to invest in BH because, say, you're really bullish on Dairy Queen, but that doesn't seem like the mistake you're describing.

jbay808
I think what GP is saying is: Google might own 4% of SpaceX, but that doesn't mean that 4% of Google is SpaceX. Approximately 0.2% of Google is SpaceX. So buying Google in order to buy SpaceX indirectly is fairly inefficient.
QuesnayJr
To be fair to NASA, they would never have been allowed to pursue a Starship-like strategy. Look at the Space Shuttle, which had all kinds of requirements ladled on top of the program, such as DoD requirements.
valuearb
Remember, NASA was the one that added the DOD requirements. To increase their budget, they lobbied congress to cancel the Air Force space program to make it a captive customer of the Shuttle.
wcoenen
> * (or "we can put a couple humans on Mars for 3 days for $100 billion")*

Is there actually a NASA proposal like that? As far as I know, orbital dynamics don't allow for this. One has to wait for a Hohmann transfer orbit window to return home.

garmaine
There are faster transfer opportunities, but not 3 days. But I think he way saying 3 days of surface ops. Which is still an exaggeration. I think the NASA reference mission is 30 days?
wcoenen
I had a peek at the Mars Design Reference Architecture 5.0 [1], and under "trajectory options" they talk about two classes of missions.

"Opposition class missions" stay on the surface for 30 to 90 days. "Conjunction class missions" stay for 500 days or more.

That confirms the 30 days that you mentioned as a reasonable minimum.

[1] https://www.nasa.gov/pdf/373665main_NASA-SP-2009-566.pdf

jccooper
There is a "short stay" option, where you return on the same synod. This requires a higher-energy transfer, involving Venus on at least one leg, to get there early enough to hit the return window and also have enough time to actually do something on the surface. Apparently you can get up to 90 days in some situations, but 30 is more likely, out of a total elapsed mission time of 400-650 days.

https://nssdc.gsfc.nasa.gov/planetary/mars/marsprof.html

Of course, this in in the "resource-constrained" mode of thinking. If you allow for giant vehicles with on-orbit refilling, SpaceX-style, you just spend a bunch of energy to get there fast instead of monkeying around with Venus.

extrapickles
Also, since its mostly made from steel, it will be fairly simple (as far as rockets go) to conduct repairs, you just need a welding rod or two. This is important for early stage bases where you don't have the equipment/materials to make carbon fiber or exotic aluminum alloy replacement parts.
paranoidrobot
Given how much difficulty they've had with welds and materials to date, is it really feasible to conduct in-situ repairs without a ton of advanced equipment?
maxioatic
I feel the same way. Likely not to start but over time I think they would build up capability. I wonder how lesser gravity on Mars would help/hurt their efforts. Easier to heft heavy gear up high?

I'm also thinking on the flip side, say a Starship somehow gets irreparably damaged getting to Mars (but successfully gets there). With some basic gear they should be able to part it out and re-use the steel.

Like for a new door on all the Cybertrucks rollin' around up there. /s

nine_k
The idea of using parts of the landing unit for materials to build local structures and machines is not new. Probably, with proper planning and construction of the lander unit parts, it can be facilitated.

But you have to plan for another mission to pick up the crew, unless you're on the Moon where you could use an electromagnetic catapult to achieve orbit, and then slowly ascend to the rocket that would take you home.

maxioatic
I didn't know that. Sure, it doesn't sound like a revolutionary idea, and I'm not surprised at all its been thought of. I was basing it on the assumption there are people there already who aren't leaving. With a colony on Mars/Moon it surely becomes more useful to have a vast amount of steel to reuse than some crazy alloy.

Electromagnetic catapult, huh. Sounds fun as hell.

grey-area
The difficulty is making it light and strong. If you're doing an emergency patch repair on a small area you could sacrifice some cargo and use much thicker material and more welds to be sure it will hold. It wouldn't be easy but is much easier than the initial build.
AstralStorm
Most importantly, you mostly need it light to escape Earth's atmosphere. (And somewhat to have enough fuel.)

On Mars, Moon or in space this constraint is reduced.

daniel_reetz
The difficulty is making a weld that doesn't weaken or anneal the parent metal through heat induced material changes.

Welding thick to thin is nontrivial because of the different heat input required in each substrate. You tend to burn through the thin part.

Patching may be possible but thick patches don't make things any easier.

ColanR
That's what I was thinking. At the very least, they'll either have to come up with some very fancy welding rod matrials, or train their welders in some interesting techniques. Reminds me of the difficulties in welding aluminum.
nine_k
Still it's much easier to work with, compared to titamium, to say nothing of carbon fiber composites or silica-fiber tiles like the Space Shuttles used.

That is, something you can have a fair chance of fixing while in orbit or on Moon or Mars.

extrapickles
It probably depends on what needs repairs. Repairs around the fuel tanks will be difficult as they would not readily have the equipment to purge the tanks of the fuel/oxidizer. Anything that is bulk structural is likely to be repairable to some extent.

I would not be surprised if part of the reason for building these in a tent is so they can gain experience for building/repairing these rockets with as little infrastructure as possible.

sabujp
Future of space as presented in shows like the Expanse. controlled by trillionaires and their companies and powerful people in governments all killing each other over space rocks. We're a long way from Star Trek, that's going to take a more fundamental advance not at all related to technology.
bluGill
Many of the colonies that make up the US and Canada were at one time controlled by the rich elite of the time. A few hundred years and they rebel to the point nobody even remembers them.
sangnoir
I'm not sure why your statement is in the past tense.
jdm2212
That's actually the backstory of The Expanse. Earth colonized Mars, Mars eventually rebelled, and the resulting Mars-Earth competition to colonize the rest of the solar system drives much of the story.
zhoujianfu
For Star Trek we just need SpaceX + UBI!
mulmen
And Vulcans.
octaveguin
The Expanse also has UBI on earth. With it, most people still lack opportunity and live a rather destitute, powerless life.

Seems like a pretty good perdition of our future, really. UBI recipients with no labor of value to offer won't have power to change their government for long.

It's unfortunate that the authoritarian future of Star Trek probably wouldn't lead to paradise. Or at least, that's how our culture's view of the future has changed.

Both fictions are a product of their time. I still wish we had the optimism of Star Trek now.

zizee
In The Expanse, the main reason for complaint from earthers seems to be caused by overpopulation which leads to difficulty in obtaining realestate and the benefits that landownership brings.

If UBI was implemented as in The Expanse (food, shelter, and meds are free), I would expect the population of the earth to plummet. The UBI would allow for more people to pursue learning and educating others. It has been shown that when people feel safe from threat of violence and starvation, and when they are more educated, the desire to breed decreases.

On the flip side, perhaps knowing that you are off the hook for paying for the expense of many children would increase the desire to reproduce?

TomMarius
Was it really shown? Is there a single country that did not replace stress of violence and starvation with economic stress? Do we have at least one larger example of what would happen if the general population was rich?
mschuster91
> Do we have at least one larger example of what would happen if the general population was rich?

We have birth rate comparison between "first world" and "third world" countries plus migration experience studies (basically, even one generation after migration from a poor to a rich country, there is a massive drop in birth rate, and after something like 3 generations the birth rate is equal to the rest of the country).

Additionally, there is a noticeable drop in birth rates when a whole country gets richer.

nkingsy
The simple explanation for these numbers is that rural children are economically useful, while urban children are a burden.
TomMarius
What country are you talking about? I don't know a single one where the majority does not feel financially stressed with too many children. (usually more than 3, but even 2 is too much for a lot of people, in many countries for the majority, probably including the United States).
jkn
Star Trek's society is collectivist (as all societies are, to a degree), but is it authoritarian?

I suspect that summarizing collectivism as authoritarian is like summarizing libertarianism as selfish: they go well together, but you can also get one without the other.

I don't know Star Trek very well, but as a utopia I guess they imagine a form of collectivism that largely preserves individual freedom? Of course most of the show centers on Starfleet, an authoritarian organisation like any military, which doesn't tell much about the whole society.

ncmncm
Anything said about libertarianism is necessarily hypothetical, because it has never happened. If it ever did, it would instantly dissolve into something certain to be very unpleasant for almost everyone.
ericmay
Hmm. Are you sure you understand libertarianism? I’m also unsure of your claim here about “libertarianism” dissolving into something unpleasant. Unpleasant in what way? Why would it “dissolve”?
TomMarius
It happened in the United States before the first world war, and continued for a few decades after that. Pretty long time to be called "immediately". While it was unpleasant from our current POV, it was way better than anything else at that time, and didn't end because it dissolved, but because the world wars needed funding.
ncmncm
I see that you are not up on the Sherman Antitrust Act. Go ahead, I'll wait.

The 1890s demonstrated what a Libertarian regime would dissolve into, instantly: Absolute rule by the biggest dog. It has happened myriad times in human history, from all kinds of pre-conditions. We were lucky, 130 years ago, that the armed forces still believed in voting. Not sure they still do...

plutonorm
I think the star trek universe is highly democratic.
ben_w
Trek is a mirror of Earth geopolitics from an American perspective in whichever year the show was written.

TOS-TNG: Klingons were Soviet-Russian, Romans were Chinese, the Federation was sexist (but much less so in TNG than in TOS) and pretended gay people didn’t even exist.

DS9: Lesbians and trans people exist, but only as exotic outsiders. Bajor feels inspired by Tibeten Buddhism and the final parts of the Northern Ireland Troubles.

VOY: ???

ENT: Nostalgia gone wrong followed by 9/11

DIS/PIC: Oh no Cold War enemies are a threat again / Oh no A.I.

kiba
IIRC, UBI in The Expanse is not really UBI, and more like minimum amount of services to keep you viable, and extreme scarcity of training.

There should really be no reason that people can't be trained or educated even if most of the skills are utterly useless in the face of automation.

h0l0cube
Also The Expanse isn't facts.
bigbizisverywyz
But in some way it may still influence the future.

If the negative aspect of the future portrayed in the Expanse are culturally absorbed, then there is a strong possibility that the people dreaming of and building the future could see that as a road sign to help them avoid that future.

E.g. it makes the point that we would need to work out ways to create better habitats in space and to concentrate on making a workable biosphere where enough food can be cultivated and raised (yes, cows in space) to survive.

kiba
I find the tropes presented in fiction misleading or unlikely to reflect reality once further examined.

Misleading road signs about the future may be worse than no signs at all.

nubero
I’m glad that not everyone in human history has shared your bright outlook, otherwise we would still live in caves…
menybuvico
I'd prefer corporate warfare in the Asteroid belt over international conflicts in Earth.

Regardless, unless we manage to come up with a new system that actually works, chances are that commercialization of space is one of the few ways for us to establish a presence off this planet.

verytrivial
"Oh, you thought this bright new future was FOR YOU? Oh, ho ho ho! What on Earth made you think that?"

You have to keep an eye on power structures.

kieranmaine
Could it be the case that a bright outlook leads people to overlook issues that need to be addressed. Maybe a more depressive (or realistic) disposition motivates people to enact change.
sekai
Let's look at this way, humanity needs to become multiplanetary species to prevent extinction if some sort of cataclysm happens on Earth: nuclear war; Yellowstone erupts, etc. Compared to that, any other problem seems insignificant.
nfoz
This will sound weird, but I have no idea why anyone cares about the abstract "survival of human species". I care very deeply about the lives of people actually living here right now. But if Earth is wiped out, what does it matter that some humans are alive somewhere? Except of course that I'm glad for them that they didn't get killed. But we're talking about generations from now anyway, and there are more direct ways to stop people from dying here today.
swader999
Because our code must live on.
sangnoir
What possible cataclysm could make Earth less habitable than Mars? If humans can figure out the tech to live in hostile environments, why not do it right here on earth without having to worry about the rocket equation and only transporting a minute fraction of humanity?
sekai
Because it's not the end? I think we strive to continue on into the unknown.
koalala
Because we are all genetically related, and humans, like most or all organisms, care about their genetic code surviving.
Koshkin
It may be not obvious (yet it should be if you think about it), but humans, in a very essential way, are not like most all organisms, and "genetic code surviving" is not our primary concern.
runawaybottle
Because it’s mostly a lie people tell themselves, similar to ‘I’m sure I am a good person’. How are you so sure?

There’s a lot of evidence that points to the fact that on a global scale, we can barely care about stuff geographically adjacent to us, or worse, socially (class) adjacent to us, but here we are claiming we care about generations beyond us.

Big old lie.

menybuvico
There is the more generic idea of leaving a track in history, making sure one's offspring survives. If one of my descendants make it off-planet and thrives there once the Zombies attack/the meteor strikes/the nukes go off then my line will continue. I have no logic explanation for wanting to continue my bloodline, but I guess it's just a natural instinct.

The second reason to get off-world is the more far-fetched one, but assuming we can establish that other worlds are dead or sterile then we are free to customize it as we please without having to feel bad about it. In the long run we could leave Earth completely, allowing whomever comes next to develop freely without our intervention.

hnrq
I hate this argument. There is no foreseeable disaster that would make Earth less habitable than any other solar system body. Even if every nuke we have was detonated, it would still be orders of magnitude easier to survive on what remains of Earth than to live in Mars.

I'm not saying there are no existential risks at all, but being on other planets would not make us any more likely to survive to them than to simply being very well isolated on Earth (which would cost 1000x less).

Developing space technology already has all sorts of benefits and it doesn't need this poor argument in its favor.

nitrogen
Every comment of this nature overlooks the challenge of politics and territory. Any significant social experiment is basically impossible on Earth because every space and person is claimed property by an existing state.

Mars would also offer cultural redundancy. Also, sometimes people choose to do things brcause they are hard.

sangnoir
> Every comment of this nature overlooks the challenge of politics and territory

If I were a betting person, I'm not sure I'd go all-in on a CEO-Emperor-King of Mars over existing nation-states on Terra

UnFleshedOne
Is that a bet on a basically functional society, or a bet on which place is better to live in for individual?
pharke
It's not a matter of Earth becoming uninhabitable. You're right that it would take a lot to do that, though it is possible with a large enough asteroid or some unexpectedly fast acting runaway greenhouse effect. The problem is of human civilization continuing at its current level and continuing to advance. Any number of small disasters could set us back hundreds if not thousands of years. We have direct evidence and record of this happening multiple times throughout human history so we know it can and probably will happen. That's why we need a self-sustaining society elsewhere, preferably far enough away to resist whatever disaster causes Earth to fall.
UnFleshedOne
But only if you already developed technology needed to survive on mars and have an industrial base not touched by those nukes.

Having a self-sustaining outpost somewhere other than earth is valuable not only for its own sake, but also due to the developed technology and industry and infrastructure implied by its existence.

If tomorrow you suddenly need a huge fleet of fully reusable ships for some reason, the right time to start working on them was 20 years ago, or as soon as basic science and technology level allow.

There are also political risks (we are all too close to each other).

Koshkin
The fact is, and it may sound like a paradox, that, for more than one reason, it is the humans themselves that is the biggest danger to their own existence in the long term.
menybuvico
Well, there is the question of whether we will ever have the possibility of developing this technology again.

I see no immediate risks to life on Earth, and considering we're quite hard to get rid of, I suspect the human race will be here for quite some time yet. The ability to do a large-scale settlement on other planetary bodies on the other hand, might go away considerably sooner, and who knows if/when we will be able to do it again if we ever end up in a situation where it might be needed.

Regardless, there are other reasons, as you say. For one, space-based manufacturing would allow us to increase the standard of living on Earth without having to worry about things like CO2 levels and pollution. If we start commercializing space then I expect colonization to follow as a natural result of that and we won't have to worry about the more philosophical side.

reddog
If there was a full scale nuclear war. And then the next week the Yellowstone super volcano erupted. And then the week after that an asteroid as big as the one that killed the dinosaurs hit Eurasia, earth would still be wildly more habitable that Mars.
stallmanite
And after a collision like the one that created the moon? How habitable during a gamma ray burst?
Koshkin
... and wha' if Earth jus' 'splodes one day... (takes another sip)
UnFleshedOne
That's a bit too much, but we still have a few month left in 2020...
h0l0cube
Life will go on in other parts of the universe, and all life, no matter where they locate themselves, will have some kind of existential threat.

And it doesn't matter how many Dyson spheres are made, if humans aren't dedicated to improving the collective opportunity to live life without suffering, there's little real 'significance' to extending the project of humanity compared to any other life-form.

ZitchDog
I’m sure you’re right, although I’m not convinced that anything like human consciousness will be reproduced, which is a shame.
bbojan
How do you know there is life in other parts of the universe?

Do you at least consider a possibility that life originated only once?

h0l0cube
Let's say by chance we discover an oracle, that could reveal with perfect certainty whether life existed anywhere else in the universe. I wager, that if I made some non-trivial wager with any other reasonable (and educated) person holding this contrarian view, they would back down before the oracle revealed its answer.
shdh
> improving the collective opportunity to live life without suffering

You cannot eliminate suffering.

> Life will go on in other parts of the universe, and all life, no matter where they locate themselves, will have some kind of existential threat.

There's no guarantee or evidence that there is sentient life in the universe

h0l0cube
> You cannot eliminate suffering.

!= improving the collective opportunity to live life without suffering

> There's no guarantee or evidence that there is sentient life in the universe

https://news.ycombinator.com/item?id=24067017

mensetmanusman
Yes, there is interesting research in evolutionary reasons for human depression, and its role in giving people needed tunnel vision to focus on the self.

Of course, this machinery can be medically disrupted by toxins and genetics (air pollution has an impact for example, lead ions, etc.), but there is a ‘healthy’ reason for depression (similarly there is a ‘healthy’ reason for ‘scabs’ and physical wound healing).

Most people in the modern era with ‘healthy’ depression are medicating away the effect (you will be shocked if you look into the rates of antidepressant usage in France for example), and this diversion can inadvertently prolong the depression as would be expected (e.g. dealing with symptoms and not cause).

Lots of interesting research in this area.

tl;dr yes, depression and depressive thoughts are useful for humans in certain cases, which is why we have them

Robotbeat
If let free to roam intellectually without hinderment, I think such a viewpoint leads to nihilistic cynicism, not constructive action.

Which isn’t to say a tempering perspective isn’t at all helpful, I just think in the absence of all optimism (& hope), there’s no room for constructive change

To illustrate, your viewpoint seems consistent with the statement: “There can be no great progress, no humanity taking root among the stars unless led by monstrous men.”

I hope you don’t consider this a straw argument, but it’s worth considering. To believe that statement is to either believe that a “good” future is necessarily one of stagnation and extinction (whether in 1000 years or 500 million years) OR to excuse the actions of monstrous men. A pessimistic, cynical perspective means no counter-movement, no inclusive cooperative with the goal of space settlement. This isn’t exactly motivating.

(And to be clear, from the perspective of history, I do not consider Elon—definitely not perfect—to be monstrous. Neither is SpaceX the work of one man. Gwynne Shotwell is as much the leader of SpaceX as Elon is—although you wouldn’t know it by reading headlines as she doesn’t care for the spotlight—plus thousands of passionate workers (who are co-owners) who believe in this vision and many of whom would be pushing for it even without Elon’s leadership.)

Mizza
I recently read the screenplay to 2001.

An interesting thing mentioned in the script, but not shown in the film, is that all of the images of beautiful space ships in the early sequence of the film are in fact space-based nuclear missile launchers, and that there are 27 nuclear nations with space weapons.

I sometimes imagine what an alien visitor would think about us if they came to our planet and saw that we had such destructive technology, pointed at _ourselves_.

rrrrrrrrrrrryan
Any sources for this? Wikipedia seems to state there are no known operative orbital nuclear weapons systems: https://en.m.wikipedia.org/wiki/Space_weapon#Space-to-Earth_...
nick_kline
They mean missiles on earth just as we have today, not space based ones.
samcheng
The poster is describing the future imagined by Arthur C. Clarke and Stanley Kubrick in 1968, not reality.

We ended up with a lot fewer nukes, and a lot less space. (Also fewer trippy alien wormholes.)

octaveguin
They might see their own past.

It seems likely that all species that make it to space might have similar pressures because they have a similar environment.

See convergent evolution. https://en.m.wikipedia.org/wiki/Convergent_evolution

That is, if they exist at all. Maybe we all converge to the great filter.

mpweiher
> game changer

Absolutely, and the quantitative analysis is just stunning.

In 2018 all of humanity launched a total of 111 payloads into space (out of 114 attempts). At around 5t per launch, that would be 555 tons.

Starship is supposed to have a payload to LEO of > 100 tons. So 5-6 launches would handle all of that, by weight.

But SpaceX says their goal is to fly these up to 3 times a day. So let's assume they can do this 300 days a year, that would be 900 launches per year. If they have a half dozen in operation, that would be 5400 launches per year. Of 100 tons each, or 540 kilotons. That's 1000x what the whole planet launched in 2018!

In other words, the entire current launch capacity of the whole planet is 0.1% of the capacity of a fleet of 6 active Starships.

And they're building an assembly line for them.

"Game changer" is absolutely right, but doesn't really convey the magnitude of the change. It's truly astounding.

joakleaf
Indeed these numbers are impressive, but can it even be done?

Is it even possible both in terms of climate change/overall environmental impact, and in terms of how much methane (fuel) we actually have.

Elon Musk's vision is getting 1 million people to Mars (if I remember correctly) within this century. 100 per starship will require 10000 launches. Distributed over 70 years, that's about 1300 Martian voyages per year.

So approximately 3 per day. Each of those launches, however will require launches of refuelling tanks (is it 6 each?)... So we are talking 19 launches per day just _people_ going to Mars!!!

Sorry, but isn't that completely impossible!??

Not just for the required fuel and environmental impact, but also given how often they just postpone basic launches due to weather.

wongarsu
Methane can be synthesized from CO2 and hydrogen. Going this route could potentially make the rocket fuel carbon negative, since the rocket will carry some of the carbon outside the atmosphere. Supply is basically unlimited as long as we have CO2 and water.

Currently we postpone many launches due to an abundance of caution. As spaceflight gets more routine we will increase our risk tolerance and launch in worse weather.

pacificmint
> we are talking 19 launches per day […] isn't that completely impossible!??

The US uses over 20 million barrels of petroleum every single day. We have 44,000 airline flights every day.

I think 19 starship flights won’t even move the needle.

Someone
https://en.wikipedia.org/wiki/SpaceX_Starship says a starship uses 3,400,000 kg (first stage) + 1,200,000 kg = 4,600,000 kg of propellant, both methane + liquid oxygen.

Let’s guess making the fuel takes 5,000,000 kg of oil (corrections welcome. I guess that’s a reasonable estimate. Less than 100% of fuel is methane, but the specific energy of methane is about 20% higher than that of oil, and creating liquid oxygen takes energy, too)

Multiply by 19 gives you 95,000,000 kg, or about 700,000 barrels. That’s 3% of the oil usage in the USA.

And that excludes construction, maintenance, and ground operations.

⇒ I think it would move the needle, more so given that we should work hard on getting that number down.

ben_w
Why count oil as the energy source for liquefying oxygen? Why not PV? Why not use natural gas instead of cracking oil?

Also, separate point: Starship return flight to Mars requires large-scale manufacture of methane from atmospheric CO2, using solar (or technically nuclear, but I don’t see that happening in this case).

It’s the only way of getting back — their tanks are empty when they finish landing on Mars — but it works fine here too.

Tuna-Fish
> corrections welcome.

Methane is not made from oil. It's either directly pumped out of the ground as natural gas, or collected from organic decay processes. Methane is more carbon-efficient, as it has almost 2x more hydrogen per carbon compared to longer hydrocarbon fuels, and most of the energy in the molecule is in the hydrogen, to the tune of 40% more energy per ton of CO2. One ton of methane burnt produces ~2.7 tons of CO2 (and 2.2 tons of water), compared to one ton of octane producing 3.1 tons of CO2 (and 1.4 tons of water).

Of the propellant in the rocket, less than a quarter is methane, and more than 3/4ths are LOX. The stoichiometric ratio would be ~1:4 (by mass), but for various reasons most rocket engines are more fuel-efficient when burning fuel-rich, so the real ratio is probably somewhere between 1:3.6 to 1:3.8. The energy cost of producing LOX is really, really low, less than 1% of the energy content of similar mass of methane. Also, this process is done with electricity, and is very amenable to intermittent production. (So the CO2 impact is effectively zero).

Coming from the other direction, according to the department of energy, the US yearly CO2 emissions from all anthropogenic sources are ~6.7B tons of CO2 equivalents, while the launch of a single SS/SH produces about 2700 tons. If you were launching a thousand of them every year, they would account for 0.04% of emissions.

credit_guy
Emissions calculation for Starship:

- each starship burns 4600 tons of methalox fuel

- the mixture ratio of the propellent is 78% O2 and 22% CH4 [1]

- that means that each 100 tons of methalox results in 53.6 tons of CO2 and 2.5 tons of CH4

- generally in the climate science it is accepted that one ton of CH4 is equivalent to 25 tons of CO2

- overall, each 100 tons of propellent will produce 116 tons of CO2-equivalent emissions

- a single launch of 4600 tons propellent will result in 5.34 kT CO2 emissions

- if we get to 5000 launches per year we end up with about 25 MT of CO2-equivalent emissions

- the current worldwide level of emissions is 45 GT CO2-equivalent as of 2017 [2]

- that means 5000 launches will increase our global emissions by 0.06%

[1] https://twitter.com/elonmusk/status/1258580078218412033

[2] https://en.wikipedia.org/wiki/List_of_countries_by_greenhous...

sobani
> the propellent is O2 and CH4 [1]

> that results in CO2 and CH4

The chemical reaction of O2 + CH4 -> CO2 + CH4 does not compute.

More likely is the reaction 2 O2 + CH4 -> CO2 + 2 H2O.

So no methane emissions, that's the actual fuel. Only CO2 (and water) emissions.

credit_guy
Sorry, I skipped some steps in my calculation.

The chemical reaction is indeed CH4 + 2 O2 -> CO2 + 2 H2O. So, for each 16 grams of CH4 you get 64 grams of O2, that's a stoichiometric mass ratio of 1:4.

The fuel ratio for the Raptor engine is 22:78, according to Elon Musk's tweet. So, for each 100 g of propellant mixture you get 19.5 g of CH4 to burn using 78 g of O2 and you are left with 2.5 g unburned CH4.

I simply neglected the H2O resultant from the reaction because, while H2O is a very potent greenhouse gas, it has a fast cycle in nature (rain, etc). Also, I have no idea how to account for it as a greenhouse gas.

bryanlarsen
From what I've heard there is a significant fraction of carbon monoxide in the exhaust, so there will be a lot less CH4 in the exhaust than you have calculated. CO is only a weak greenhouse gas.
credit_guy
That is very interesting. Do you happen to have a link? I'm not doubting you, I think you are right, but a link that goes into this type of detail would be a very interesting one to read.
bryanlarsen
I probably heard that here: https://everydayastronaut.com/rocket-pollution/

Otherwise it would have been in a comment on an Eric Berger Ars Technica article.

lfuller
This doesn’t take into account that the methane used in fuelling can be extracted from the atmosphere and that much of the fuel / oxidizer mixture actually is removed from Earth entirely.
Tuna-Fish
> Sorry, but isn't that completely impossible!??

> Not just for the required fuel and environmental impact, but also given how often they just postpone basic launches due to weather.

The environmental impact of a rocket launch is roughly in the same category of the environmental impact of a airliner doing a single long-distance trip. (I did this calculation for F9, SS/SH would be higher but not more than two orders of magnitude higher.) Pre-covid, there were approximately 100 000 airliner flights a day. You do the math.

And that's before we consider that they are fueled with methane, and that there are sources of methane that are potentially not just GHG-neutral, but GHG-negative. (Collecting agricultural methane emissions and burning them is dramatically better than releasing them directly.)

As for weather, it is possible to launch rockets in very bad weather, for example the Russians frequently launch in literal blizzards where no winged aircraft could fly. It's just that ability to fly in inclement weather is something you need to design for -- rocket bodies are generally not strong against transverse loads, and this is made worse by having a high fineness ratio. SS/SH, being much more stubby than most current American rockets, will be much less impacted by weather than them.

chrisjc
Perhaps a stupid and naive question, but is there even the demand to lift that much mass into orbit? I may just be lacking in imagination.

Obviously most of that mass would have to leave orbit in order for it not to end up looking like an LA freeway in rush hour.

edit: i guess propellant/fuel would be one of the heaviest and important payloads we would need to get up there.

jvanderbot
I read once that with a 100m telescope, we can image continents on exoplanets. We could construct a 100m segmented telescope in orbit, if only we had sufficient launches to get all the segments up, and sufficient capacity to send the assembly robots / astronauts. Today's tech, launch limited.

Here's a writeup: https://exoplanets.nasa.gov/internal_resources/1375/

In general, once you get to LEO, you're half way to anywhere ... That is, getting to low earth orbit is half the battle. Spacex will remove that battle for everyone, making space expansion and exploration 2x easier.

My dream is earth-orbiting shipyards for outer planet missions and interstellar missions. There's nothing stopping us but will.

baq
starlink/oneweb/similar constellations, assuming US folks really hate comcast as much as they say on the intertubes. these are up to 12k sats with very short (couple years?) life time, so regular flights will be necessary to keep the fleet at desired capacity. this beast can lift i-don't-even-know-how-many hundreds of birds in one go.
mpweiher
One Starlink satellite is apparently 250 kg at this time. They currently get sent up using Falcon 9, which can lift 15t to LEO when reusable, so that checks out.

At 100t, that would be 400 a pop.

mpweiher
> demand to lift that much mass into orbit?

Well, 1 million people ain't going to get to Mars by themselves[1].

But once you have that sort of capacity, at those sorts of prices, many things that are now unthinkable become very possible and possibly useful.

Asteroid mining has been mentioned. Putting huge telescopes into orbit or the Lagrange points. How about a nice and big radio-telescope on the far side of the moon, where there is no EM interference. Or maybe even further out? How about some very, very long baseline-interferometry[2]?

Put manufacturing in space. There appear to be some useful materials that can only be made in low-gravity environments, but currently the Price is not Right™[3]. Bezos wants to put large space habitats into orbit instead [4]

Others have mentioned Starlink, with up to 12000 satellites. Nowadays they're talking about 42K satellites.[5]

Space-based solar power might become feasible[6]. Maybe put up a sunshade[7] to control global warming.

How about some manned deep-space probes? Maybe with some Vasimir rockets[8], a nuclear reactor and lots of reaction mass.

We are so conditioned to think that anything space has to be small, super-lightweight and super-high-performance/expensive that it's really kind of hard to think about the consequences of those constraints no longer applying.

And of course tourism, like the already-announced circumlunar flight[9], space habitats etc.

Think big!

[1] https://www.syfy.com/syfywire/elon-musk-mars-colonization (or just google it)

[2] https://en.wikipedia.org/wiki/Very-long-baseline_interferome...

[3] https://en.wikipedia.org/wiki/Space_manufacturing#Materials_...

[4] https://www.businessinsider.com/jeff-bezos-proposes-floating...

[5] https://observer.com/2019/10/spacex-elon-musk-starlink-satel...

[6] https://en.wikipedia.org/wiki/Space-based_solar_power

[7] https://en.wikipedia.org/wiki/Space_sunshade

[8] https://en.wikipedia.org/wiki/Variable_Specific_Impulse_Magn...

[9] https://en.wikipedia.org/wiki/DearMoon_project

greycol
With out current capabilities space only offers intangible services to earth (not to discount them as they are still profitable markets). With the step change in capacity we can start talking about getting equipment into space to bootstrap making it physically productive for earth.

We can start looking at the infrastructure that makes moon or asteroid mining for fuel possible. 'Cheap' fuel in space is the dream because it means asteroid 'mining' for materials that get returned to earth can be profitable (massively profitable to the point of dwarfing any investment currently made).

But the amazing side effect is suddenly we also have materials in space that like the fuel now costs orders of magnitude less than if we were sending it up. It'll becomes viable to build more infrastructure in space and so (perhaps ironically) there will be more demand to get materials from earth to space.

Diggsey
What you don't get a sense for in the video is the size of this thing... It's absolutely bonkers.

9m (30 ft) in diameter 50m (160 ft) in height (or would be with the nose-cone)

That's the height of a 12-story building. And this is the upper stage of the full rocket.

sneak
...with a 22 ton steel weight (that little block) on the top of it, in addition to the entire weight of the test article and the fuel.
m4rtink
There is likely very little fuel though for such a small hop.
KiwiJohnno
I read somewhere it had about 15 tonnes of fuel onboard, which isn't trivial
invisible
Just a slight correction: this prototype is 30m tall. Still absolutely bonkers how big this is and ALSO that it's not the full height yet.
throwaway0a5e
Construction equipment for scale:

https://s.yimg.com/ny/api/res/1.2/mz7KZlvgwTBa5cs4xfM_aA--~A...

deadwing0
I read that as "for sale," and was genuinely concerned for a moment that spam was being posted on HN. :D
trsohmers
For reference, the Falcon 9 FT is 3.7m (12 ft) in diameter and 70m (230 ft) in height.
swader999
The commentator likened it to flying a giant grain silo.
gorgoiler
Oh my goodness. I had heard of Starship from the initial PR, and from those photos I had somehow assumed it was about the same size as a train carriage (~60ft.)
bconnorwhite
The crazy part is that Elon has said this will look like a rowboat compared to their future rockets
shdh
Could you share a source for this quote?
bconnorwhite
https://blog.ted.com/what-will-the-future-look-like-elon-mus...

@34:15

mabbo
And it's being powered by one raptor rocket. It's designed to have 6.
_kst_
And the first stage "Super Heavy" is designed to have 31.

Update: I think the hopper in the video is a prototype of the lower stage, which is planned to have 31 engines. The upper stage is planned to have 6.

thinkcontext
The test today is a prototype for the upper stage.
mabbo
Afaik, the hopper in the video is the prototype of the 6-engine upper stage. The super heavy will actually be even bigger than the one in the video!
m4rtink
The small hopper in the video is an early general purpose prototype from heavy duty steel, what flew today is a prototype of the second stage (Starship).

But assembly enclosure for the first stage (Super Heavy) is being built already.

bfieidhbrjr
Does anyone else get super depressed by this?

I did some great work today. I coded something pretty cool and useful. I built a little deck to explain it. My coworkers loved it. My job security went up. I enjoyed it. The journey is the reward.

But these guys are making rockets in tents.

Should I be rethinking life? Because that's how it feels. I love it. I admire them. But it feels unobtainable. I want to make that kind of a dent in the universe. And yes I know it's thousands of people working there.

But still.

phtrivier
Out of curiosity and without any condescention implied, are you saying this because the business you're currently working on seems less important / relevant / urgent, to you, than space exploration ?

Because, "these guys are making rockets in tents", sure ; but, meanwhile, someone is "fixing up human beeings in an hospital", "teaching kids how to read in a school", "writing poetry in a basement", etc...

There probably isn't any objective way to rank pursuits (or at least, no "objective" way that does not end up in a dystopian society and / or Golgafrincham [1].)

And it's not like anyone is actually counting score (unless you're Chinese. Someone is counting score on you at the moment. Deities have mercy on you.)

Those precautions aside, if such an event is triggering you to pause and reconsider you life choices, than go for it ! Maybe you actually need to branch and try and get to work in space exploration after all.

And if you're not clever enough, educated enough, US Citizen-enough, etc... there are opportunities to inspire others, educate others, help others...

And in the end, just plain looking at the sky. This thing is darn cute.

Enjoy the journey.

[1] https://hitchhikers.fandom.com/wiki/Golgafrinchans

gorgoiler
Making a difference in the world is what counts. It’s the delta that matters, not the final value.

Measure what you do by the change in yourself and others, and how it makes society better.

yetihehe
Yeah, preferably that delta is positive.
fsloth
It sounds like you are not working in a field that is intrinsically motivating to you. Perhaps you should find an employer with a product whose end value you can appreciate?

For example I work in CAD. I'm just a software engineer. But the products we make help engineering companies design huge beautiful monsters of steel an concrete.

Sure, they are not rockets, but they are things that impact peoples lives.

Working on a product, that have users who you appreciate is intrinsically satisfying. At least to me.

I feel the code I write is kind of meaningless, but the work my users do is not. Hence I find meaning in their constributions.

y-c-o-m-b
> Perhaps you should find an employer with a product whose end value you can appreciate?

If only it were that simple. Sometimes the stars align and that happens yes, but for many people - especially those of us with families that can't just up and move somewhere else - it's not reality.

Let's say you reside in an area with such a job to begin with. First your resume has to be looked at, so let's assume it makes it through the various automated filters. Then it gets picked up by an actual person who glances at it for maybe 1-2 minutes tops and throws you into the "to be considered" pile. Next your resume is competing against a relatively large pool of other resumes. If it makes it through that, you then have to captivate the recruiting/hiring manager enough to move to the next step. Now you're at the dreaded technical interview where all sorts of shit can go wrong (especially since this is a highly sought position); maybe you're a little too slow at figuring something out, maybe you're not a good "cultural fit", maybe they don't like the way you look or dress, maybe you're a genius but your communication skills are abysmal etc. If you somehow make it through that garbage disposal unit then you have to talk to some manager who gauges your personality and how you handle stress; room for more screwing up. You make it through all that, but wait! You're still competing with 10 other folks that are just as good if not better than you. You get lucky and make it and get an offer letter - but the pay is dreadful and doesn't match the cost of living. Now what?

fsloth
Sure, family comes first. My intent was to imply that the space of meaningful work is plausibly a lot larger than space vehicles.

My intent was not to imply that an employee can always utilize complete deterministic agency in their career path.

gorpomon
I hear you friend, it is disheartening to see, but also heartening to see.
m4rtink
Not at all, rather I see every step on their journey as making easier for people who like space and rockets to get involved in the future, without having to win the "astronaut lottery".
menybuvico
Well, won't your pretty cool and useful code make the lives easier for some people, including yourself? The idea is to leave the World a little better place than it was when we got here, and it sounds like you just did something that will help you achieve just that.

Personally, things like this motivate me. If those guys can send a giant steel tube into space then goddammit I will be able to finish project XYZ on time, and provide a useful service to a customer, thereby contributing to the greater whole.

chasd00
every time i start thinking i'm hot shit i go watch some falcon 9 launches/landings on youtube. It's truly humbling and inspiring at the same time.
tjtrapp
We're hiring for Starship and Starlink software teams: https://grnh.se/080f65d02us

It sounds like you're passionate about your work and that's an important quality. As gorgoiler points out, "Making a difference in the world is what counts."

If you'd like to help, consider applying! :)

client4
Y'all looking for Telco people for the northern tier of the US ground stations? North Dakota is a hard place to get 100Gs wavelengths ;)
damon-
TJ, I'd like to apply for supply chain. Any expertise there?

I don't work overtime and I'm not a fan of Thai food

h3rsko
My dream is to work for spaceX, but I'm NY. Do you his have remote teams or a NY office?
jessriedel
Hopefully tjtrapp can give you more details, but I have a friend who joined SpaceX as a software developer and they are fully remote if they want to be for the foreseeable future.
0xffff2
I find it completely baffling that it's your dream to work for SpaceX but you're unwilling to relocate? I'm stuck in the bay area (which I absolutely despise) because of my job, but I get to write flight software for spacecraft so I deal with it.
cosmotron
0xffff2, you yourself just said, "I'm stuck in <location> because of <reason>." It can't be that baffling to think that h3rsko is also stuck (e.g. because of a family).
0xffff2
Yes, that's because I was using the word "stuck" metaphorically. I choose to be stuck because I actually find the benefits of being stuck to outweigh the costs. If I lost my job it probably wouldn't take me 24 hours to pack my shit and be gone. But as long as I'm here getting to do what I want to do I stay.

If you can't figure out how to move to a different state to pursue a dream, it's not much of a dream.

0xffff2
How's the work/life balance these days? Are 60-80 hour work weeks still the norm?
walrus01
Is the starlink software team based in Redmond or Hawthorne?
mulcahey
There are Starlink software positions available at both locations.

For example, here is a web development position in Hawthorne: https://boards.greenhouse.io/spacex/jobs/4682610002?gh_jid=4...

And a network position in Redmond: https://boards.greenhouse.io/spacex/jobs/4770694002?gh_jid=4...

Here is the job board for all software positions: https://www.spacex.com/careers/index.html?department=Softwar...

Allower
Sounds cool, but I value my sleep ;-)
pinewurst
The application forms are pretty ridiculous with theIr insistence on school/graduation dates (some reqs) and SAT/ACT scores (all).

As a very experienced engineer, I can’t accept being judged on (historical) trivia.

rbanffy
Same here. Understand they need to somehow weed through their applications. Experienced engineers are costly to assess and having a cheap test to remove the obvious negatives helps them at the cost of a few false ones. :-(

I'm also not a US citizen, so that's another cheap test I can't pass.

inopinatus
I've found that all really effective hiring funnels are biased for type 1 errors at the start and type 2 errors later on.

Filtering on inane academic requirements up front is the exact opposite, and you end up rejecting half the real talent pool.

skissane
> I'm also not a US citizen, so that's another cheap test I can't pass.

Unlike other "cheap tests", that one is imposed by US government regulations, not SpaceX's own decisions.

I imagine SpaceX would be quite happy if ITAR was loosened, but I doubt that will happen.

I honestly can't see why ITAR applies to citizens of friendly countries such as Canada or the UK. The point of ITAR is to stop unfriendly countries like China, Russia, Iran or North Korea getting access to technologies with sensitive military applications. The US trusts its closest allies in so many other ways (e.g. UKUSA "Five Eyes" intelligence sharing agreement, the 1958 Mutual Defence Agreement under which the UK and US share nuclear weapon design information), why not in this?

rbanffy
A country is friendly until it isn't. I understand it's not a requirement imposed by SpaceX, but it also prevents them from getting a lot of applications they wouldn't be able to turn into hires.
skissane
> A country is friendly until it isn’t

If the US can trust the UK with information on nuclear weapon designs and delivery systems, surely it can handle a few UK citizens working for SpaceX?

In the unlikely event that the UK and US had some falling out, the US government could always order SpaceX to lay off UK citizen employees.

rbanffy
And what will you do with their knowledge?
skissane
It seems rather silly to me to worry about the knowledge of a few UK citizen SpaceX engineers, in the event of a hypothetical US-UK breakup, considering how much information the US and the UK already share in the fields of nuclear weapons and SIGINT. Surely knowledge about the later two is a much bigger concern than the first? Yet, if they are willing to risk the later, why not risk the former as well?

Besides that, the risk of a US-UK breakup has always appeared to be low, and Brexit arguably makes it even less likely.

garmaine
> If the US can trust the UK with information on nuclear weapon designs and delivery systems.

Bad example. The soviets got the bomb because of British spies in the Manhattan project. After that, there was very little collaboration to this day.

skissane
What about the 1958 Mutual Defence Agreement? That led to sharing of nuclear weapons design information, over a decade after the Manhattan project.

https://en.m.wikipedia.org/wiki/1958_US–UK_Mutual_Defence_Ag...

garmaine
Read the details; it wasn’t free exchange of information. It was basically a way for the US to allow sales of some nuclear plants and material, and sharing of design work only when it overlapped significantly with what the UK already did.
skissane
Which details? Wikipedia says:

> The Americans disclosed the details of nine of their nuclear weapon designs: the Mark 7, Mark 15/39, Mark 19, Mark 25, Mark 27, Mark 28, Mark 31, Mark 33 and Mark 34. In return, the British provided the details of seven of theirs, including Green Grass; Pennant, the boosted device which had been detonated in the Grapple Z test on 22 August; Flagpole, the two-stage device scheduled for 2 September; Burgee, scheduled for 23 September; and the three-stage Halliard 3. The Americans were impressed with the British designs, particularly with Halliard 1, the heavier version of Halliard 3. Cook therefore changed the Grapple Z programme to fire Halliard 1 instead of Halliard 3.[85] Macmillan noted in his diary, with satisfaction that:

>> in some respects we are as far, and even further, advanced in the art than our American friends. They thought interchange of information would be all give. They are keen that we should complete our series, especially the last megaton, the character of which is novel and of deep interest to them.

> An early benefit of the agreement was to allow the UK to "Anglicise" the W28 nuclear warhead as the Red Snow warhead for the Blue Steel missile.[87] The British designers were impressed by the W28, which was not only lighter than the British Green Grass warhead used in Yellow Sun, but remarkably more economical in its use of expensive fissile material.

Wikipedia doesn’t appear to support your version of events. (Of course, Wikipedia is sometimes wrong; but if you think it is wrong, which of the above claims it makes is wrong specifically?)

Teever
The ulterior motive to ITAR is protectionism.
mulcahey
I would presume it depends on whom you're asking. E.g. Elon's stated multiple times that he believes requirements of degrees on many of Tesla's job postings to be "absurd"[0][1]

[0] https://youtu.be/ywPqLCc9zBU?t=2733

[1] https://twitter.com/elonmusk/status/1208841343440568320?s=20

xiphias2
Having a degree or not is different from having a degree with a low or high GPA. Having a low GPA at a University is a worse signal for hard working person than having no University background.
dmix
Does anyone even care what your grades were beyond your first job?
pinewurst
Much less one’s college admission test scores - how do they signal a “hard working person” especially 20 years down the road?
xiphias2
Why would a person with 20 years of experience want to work for a company with no work-life balance?

I prefer investing in Tesla/SpaceX instead of working there, and leave working extra hard to young people who have more energy than me.

Teever
A lot of people already work meaningless jobs with no work-life balance and they would find it to be a substantial improvement to work somewhere with meaningful work even without a proper work-life balance.
dmix
Plenty of mega-corps are full of people who phone-it-in every day, you don't have to work demanding jobs.

I personally love working hard, which is why I only work with startups, which tend to have a higher personal ROI and more meritocracy oriented.

adventured
> Why would a person with 20 years of experience want to work for a company with no work-life balance?

The initial comment by bfieidhbrjr already answered that very nicely: out of the desire to actually do something that is important re work. Important being subjective to the person in question obviously.

Robotbeat
I would apply anyway. SpaceX judges more heavily on outside projects than academic credentials.

The US citizen (and/or permanent resident) thing is probably not negotiable, though, because SpaceX does a lot of Nat Sec stuff.

xiphias2
It's OK, you don't need to. There are many companies with different requirements, so you're just probably not a good fit.
benhurmarcel
At least you can apply, you're American.
aphextron
Official video: https://youtu.be/s1HA9LlFNM0
DangerousPie
Can we change the link? This is much better.
Taniwha
So what's burning above the motor, I thought these were closed cycle engines?

Were they incredibly lucky

Tuna-Fish
There's a lot of speculation on that, it's probably either wiring/tubing insulation or paint that got ignited, or a small leak. It seems to put itself out at 0:51.
dmix
A significantly better version.
dvno42
Thank you.
handedness
Thank you. So much more enjoyable with pure audio than with commentary which only detracted from it, and the shot is spectacular.
Jaruzel
As a child I read all the Tintin books. My favourite ones were Destination Moon, and Explorers on the Moon. The rocket used in those stories is iconic. For me, Starship taps directly into those memories. I know it's infeasible, but if they ever painted the production Starships white and red, it would make me SO happy.

I'm too old now (approaching a de-orbit burn for 50) to be able to go to space, but I'm still loving the thought that my future grand-kids should be able to.

buzzwordninja
One thing I remember from those books is how they lay on their stomach during acceleration, whereas I believe all real life astronauts have been sitting, or on their backs:

http://www.projectrho.com/public_html/rocket/images/deckplan...

Which is also interesting given the recent (well... not even so recent now) discovery of the benefits of placing COVID patients in a prone position to ease breathing.

BbzzbB
What a week for SpaceX! Two days ago they landed Bob and Doug, and now they succeeded to hop a water tower (as a side project nonetheless, AFAIK only a small part of SpaceX is on this team)! Can't wait to see future iterations and improvements of this beast, especially to see more Raptors strapped on!
Robotbeat
The water tower was last year. This is a prototype using the same production technique as for the production versions.

EDIT: More grain silo than water tower. ;)

byw
Is it just me or does the workmanship look like a step up?
djaychela
They've been interating on the construction process with each one built. I've been welding (DIY) for 30 years, and the first ones looked pretty bad to me - lots of distortion, and I actually thought the first one was just a mock-up. But the process is clearly improving with each build. I still think the nose cone looks like it will improve in the future, as it doesn't look as precise as the main body is now looking, but I'm sure they're working on it.

This, overall, is an amazing achievement. I watch every F9 landing that I can, and it never ceases to amaze me. The FH two-booster landing looked like straight out of a SciFi movie. But this... this is next level again. The 20km flight will be truly incredible.

fiftyfifty
It's also worth pointing out that the new prototypes, like SN5 that flew today, are made with significantly thinner steel over what "Star Hopper" was made with last year. They have spent a lot of effort perfecting their manufacturing technique so they can make these things as light as possible and still achieve the safety margins that they need to support manned flight. That's why they need the 22 ton weight on the top for this flight, because they can't throttle a single Raptor engine low enough to hover these new designs.
erikrothoff
Elon has mentioned that it’s all hands on deck for Starship. The only resources not on Starship should be focused on making the Dragon secure and certified. https://www.cnbc.com/2020/06/07/elon-musk-email-to-spacex-em...
sfjailbird
Thank God for that guy in the corner helping me to know how to feel.

Seriously though, this has been an incredibly annoying trend for a few years, everything has to be tagged with some pre-packaged emotional reaction. Such a dumbing down of public discourse.

Someone linked the official video and it's amazing: https://youtu.be/s1HA9LlFNM0

Cogito
I mean, feel free to be annoyed with the commentary, but there was no official live stream of the event.

There were 3-4 non-official live streams, I think all of them provided by people who have streamed every single one of these tests live.

Asking those people to not have a reaction when the thing actually flies is a little far-fetched, unreasonable, and contrary to what their audience wants and expects.

This isn't a reaction video with "some pre-packaged emotional reaction", it's sitting down to watch an historical event with friends - hardly a dumbing down of anything.

Even in the official streams of other events the hosts become emotional, and are often drowned out by the cheers of those around them. I really have no idea what it is you want or expect from these live streams.

martindbp
See also "Youtube face".
smusamashah
There is also a "Dreamworks Face"
db48x
Doesn't Japanese television have a lot of reaction shots too?
StevenWaterman
The people watching that livestream are there specifically for him, he's a well-known personality in that community.

If you don't want that, there's other streams without presenters, or with less obnoxious presenters.

ChuckMcM
Always impressive to me. And I know that people will say "Yeah, basically the only thing 'new' here is the engine" but there are also a bunch of other things that struck me;

It did the hop 'off balance' (the final version expects to have 3 raptor engines working together) so the engine out scenario for landing still seems pretty safe.

There is something like four more advanced vehicles in the warehouse section at various stages of completion. So scaling up making them seems to be working out.

It looks "small" in the images but when you see people working on it you can tell its grain silo big. That is a heck of a thing to fly overhead.

Rockets taking off and landing vertical has amazed me ever since I saw the DC-X do it once.

rbanffy
The DC-X still manages to look modern next to it. Had it succeeded, it'd have done something not even SpaceX is doing, which is a fully reusable single-stage-to-orbit craft.

I don't think we have the advanced materials for that.

ecpottinger
I think the Delta-X could have done the job, what went wrong was letting NASA taking control of it. Remember these are also the people who went with segmented solid fuel boosters, these were the people who thought the VentureStar with three new techs that all had to work at the same time but rejected the designs that did not need as much new tech, these are the people who let the SLS design go forward.

The Delta-X was an interesting design until NASA was involved.

mschuster91
The Wikipedia article on DC-X is interesting.

> In a post-accident report, NASA's Brand Commission blamed the accident on a burnt-out field crew who had been operating under on-again/off-again funding and constant threats of outright cancellation.

That is the reason why SpaceX is so much more efficient and revolutionary, compared to what Boeing/ULA on US side and EADS/Ariane on EU are doing - they are cutting politics out of the equation and with it, a whole boatload of issues.

cryptonector
Contractors like Boeing for SLS generally have sweetheart cost+ deals. They have zero incentives to cut costs -- nay, they have an incentive to increase costs because their profits are the "plus".

SpaceX isn't interested in a sweetheart subsidy deal. They are competing. That's why their contracts with NASA are fixed price: it gives SpaceX every incentive to keep costs down so as to maximize profit.

Surprise! SpaceX is doing better than the competition that gets sweetheart deals. It should really not be a surprise to anyone though, but it probably is to some.

ChuckMcM
I agree. For a space craft that did it's 150m "hop" in 1992 it was even more impressive (especially considering how much the computers and IMU weighed in that thing!)

I'm not convinced though that it ever really to achieve it's SSTO goals and still land it. With on orbit refueling perhaps (as could Starship in a similar scenario). It was also shooting for much lower mass to LEO.

rbanffy
Structural weight is mostly a function of the surface area and fuel capacity and payload are a function of the volume. If you make the rocket bigger, it's payload mass fraction increases.
ChuckMcM
> Structural weight is mostly a function of the surface area and fuel capacity and payload are a function of the volume.

Agree with this.

> If you make the rocket bigger, it's payload mass fraction increases.

Don't agree with this. The way I see it, as a rocket gets bigger, and stays in one piece, its payload mass fraction decreases. The inability to jettison heavy engines and structural components means those things become part of the 'mass fraction' that ends up in orbit. And the bigger you make those things, more and more of your mass fraction is being committed to carrying stuff and less is available for non-rocket payload. Hence its a decreasing mass fraction in terms of amount of payload.

Its fun to play around with this in Kerbal but its pretty much a hard limit.

Things that can affect the mass fraction in a positive way are things like more ISP in the engines. When you look at the evolution of the Falcon 9, the increase in mass to LEO was a result of two things, one upgrading the efficiency of the Merlin 1D engine and two developing a way to put more propellant and oxidizer in the same volume by super chilling it.

rbanffy
If you look at it, chilling the fuel and oxydizer is kind of increasing the fuel capacity without adding structural weight.

I need to check my math to be sure of how much you can scale that way, but that's one of the reasons Starship is such a BFR.

iso947
In theory starship will have the delta v to get to LEO and back in a single stage, but the payload would be so small it wouldn’t be worthwhile.
garmaine
Incorrect, it couldn’t get back. The landing fuel and reentry structures would make it weigh too much. But as a demo they have considered a one-way orbital SSTO trip that’ll burn up on reentry.
rbanffy
A suborbital cross globe flight would also be quite fun, but they'd need to build a landing/launching pad and refueling station.
bluthru
Here's a video on SSTO: https://www.youtube.com/watch?v=Sfc2Jg1gkKA

Elon talking about SSTO: https://www.youtube.com/watch?v=cIQ36Kt7UVg

cryptonector
Single stage to orbit (from Earth) is not as efficient as two stages to orbit, and that's the reason it's not done. If SpaceX manages to deliver Starship and reuse it and its booster, that will be a huge improvement over any possible reusable SSTO. SSTO or otherwise, reentry and landing are difficult enough, but SSTO adds other difficult problems.
modeless
Direct link to the launch time: https://youtu.be/NJR4gZBLMNw?t=2183
valine
That was a sight to behold, history in the making for sure.

This was the first flight of a vehicle which may someday take humans to mars.

mitchellgoffpc
Man, I saw that thing moving sideways right after liftoff and I thought it was a gonner! Huge congrats to SpaceX for landing with an offset engine like that on their first try!!!
Klathmon
The single raptor engine is offset from the center on this test, so it had to do some pretty quick and somewhat dramatic adjustments to keep things upright.
9nGQluzmnq3M
Why is it offset from center? To stress test the steering?
Cogito
The 'thrust puck' the engine is mounted to is designed for multiple engines, none of which are in the centre.

They are only using one engine this test, but are testing the flight-design thrust puck (as opposed to some interim structure with a centre mount for the single engine).

gpm
It's designed for 3 sea level engines and 3 vacuum engines to be installed in a radially symmetric fashion... But they only installed 1 sea level engine on this prototype.
floatrock
There's some center-of-gravity and shifting of things as you burn up fuel. Not an expert, so here's where the streamer talks a bit about it, including why the space shuttle did it too: https://youtu.be/NJR4gZBLMNw?t=1195
ncallaway
The design of the full rocket doesn't have a single center engine. Instead, it has three engines at the center.

This test article uses the same layout for engines, but with one engine instead of three. So that one engine is offset from the center.

Their flight software is already capable of handling the multiple engine out-scenario and compensating for it, so there's no real reason for them to center the engine for the test article.

allenrb
Same here. I was waiting to see if it would cross the point of no return and obliterate their ground facilities... again. Instead, looks to have been a nearly perfect test. Onward!
Tuna-Fish
It did obliterate their launch stand, with the flame of the raptor cutting through a thick steel beam, and you can see walkways being tossed about at ~0:12, but they have parts for 3 of those already on the site.
Cogito
In addition to the other replies, it is also standard for rockets to 'clear the pad' as soon as possible, to avoid damaging the ground support equipment as much as possible.

The amount of kick to the side is almost certainly due to the offset engine, but they would definitely design the flight path (with that in mind) to clear the pad as fast as reasonable as well.

m4rtink
Yep, pretty much every rocket is much much cheaper than the often one-off launch infrastructure.

From what i remeber some Soviet rockets had after a string of pad destroing failures any abort commands disablee for the first 30 seconds of flight - regardless of what happens, it must not hit the pad, or Barmin (the chief designer of most Soviet launch complexes) will be angry and you don't want that.

daveslash
This might be petty and off topic, but do others find this sort of streaming-commentary off-putting? I don't so much mind the informational commentary, but the emotional outbursts of yelling, hooting, and hollering is just... not for me and really makes me want to mute the video. Like I said, maybe off topic, but I see this becoming more and more common and wanted to know what people here think?
doomlaser
This is the first time I've seen video of a starship test that didn't end in catastrophic explosion, so this is great news!

I'm still worried about the overall design, specifically when it comes to landing. The current procedure is for it to fall into the atmosphere flat on its side, then continue to fall for a long time, and then only when it's near the ground it must reorient 90 degrees to upright and then do a final suicide burn to land. It seems like it has too many chances to fail with no recovery, but I'm no rocket scientist.

jccooper
Good news is, this is next on the test program. They'll be testing the "belly flop" with this vehicle in the next few flights. So they'll see any problems with it before they get too far.

I don't see much reason to be worried about changing orientation in the long term. It's not in a particularly exotic flight regime (subsonic, lower atmosphere) and so long as the vehicle has sufficient control authority (and it will) anything that would cause that maneuver to fail would cause any other maneuver, like landing, to fail as well. The F9 actually already does a (less dramatic) version of this, and has never had a problem in that phase of flight.

lmm
Parachutes are a lot fiddlier and less reliable than the layperson assumes, so the baseline for how complex a system like this can be is worse than you'd think.
doomlaser
In my mind, the multiple complex reorientations while falling at terminal velocity — with no plan B — just seems particularly harrowing..
anticensor
Plan B is one more orbit and try again...
doomlaser
Once you've entered the atmosphere, you're falling to earth whether you like it or not. As it stands now, you must execute every move in the procedure or you crash into the ground at 120mph and explode.
Laremere
Doing it once is harrowing. Even doing it the tenth or the hundredth time might be harrowing.

Doing it the thousandth time is starting to get old. Doing it the ten thousandth time is business as usual.

The place to improve from is not as good as you may think, "On the Demo-2 mission, NASA has estimated a 1-in-276 chance of losing the crew at some point." Once you have full re-usability, you can fly rockets several orders of magnitude more times. When you're flying that often, you have the ability to work out the kinks.

If instead you limit to what today feels the safest, you might limit yourself from full re-usability and eventually being much safer.

If you want to still go for full re-usability, adding a backup system might actually make things more dangerous: It's another thing that has failure modes. Redundancy can be a double edged sword.

imglorp
To be fair, the hopper 150m test was ok. That was scaled down but retired risk for the raptor engine and fuel and controls. The full size is the same thing but with more structure and stress issues.
bob33212
It is a safer design because it is just 1 piece. There are a hundred ways it could fail. But that is within 1 system. Not multiple systems
avernon
One thing to think about is that the heating/energy is exponential. So doing the belly flop lowers the heating and the energy the rocket is carrying quite a bit.

Planes make 90 degree turns all the time! And in actuality this rocket could be less complex than a modern airliner as far as number of parts and processes.

They have taken huge leaps in engine technology with Raptor that allow for a lot of simplification across the rest of the rocket and which could make it airliner level safe someday.

rbanffy
It'll still be fun to hear the pilot announcing to the passengers that "We are now preparing for the suicide burn. Please make sure your seatbelts are fastened and your trays are securely stowed away. We wish you an enjoyable landing. Thank you for flying SpaceX".
mchusma
Congratulations to SpaceX! Helping make the pandemic more bearable one hop at a time.
api
So much less sooty with methane instead of kerosene!
modeless
It's not just the fuel but the way it's burned. The older Merlin engines don't burn all the fuel, by design. The new Raptors do, and it's actually quite an achievement. More information than you ever wanted to know about it is here: https://everydayastronaut.com/raptor-engine/
zionic
https://www.youtube.com/watch?v=s1HA9LlFNM0

Is a much better video :)

snoshy
Pretty wild. Seems like it took out a chunk of the pad on the way up as well. Those Raptors are no joke.
Ajedi32
Official video from SpaceX: https://youtu.be/s1HA9LlFNM0
zionic
This should be the link, it's way better!
fnord77
Is there an official spacex feed?
snoshy
There was not. They typically don't provide one for tests, especially as these hops are relatively minor compared to getting to orbit. It's likely they'll provide one for the 20km hop coming up, since amateurs and fans aren't going to be able to set up their own feeds much further.
Ajedi32
They actually posted an official video of the hop just now: https://youtu.be/s1HA9LlFNM0
Robotbeat
No, but there were no fewer than 3 hosted live-streams (one which had 3 different HD live cameras you could switch to) with countdowns and technical commentary. All by non-traditional media. Remarkable what is possible nowadays.

Here they are:

https://www.youtube.com/watch?v=VwC6LG_z8zE

https://www.youtube.com/watch?v=NJR4gZBLMNw

And the last one is constantly streaming 3 live feeds of the SpaceX Boca Chica facilities 24/7:

https://www.youtube.com/watch?v=5QbM7Vsz3kg

EDIT: And by remarkable, I don't just mean technical capability but the really impressive non-traditional media community that has grown up around New Space the last 5-10 years. Here's amazing, close-up 4K video of the hop by yet another non-traditional space media person:

https://www.youtube.com/watch?v=HXzPu6MM99Q

ackbar03
What was the context behind this launch? Did they just luanch a grain silk just for kicks or something? That can't possibly be the new design for a rocket
ekimekim
It's a prototype to test the materials, engine, process etc. Since it's only ever going to do little hops like this one, it doesn't need to be aerodynamic.
dencodev
It's not clear to me why you need to spend so much fuel hopping around on Mars or the moon.
thinkcontext
They are testing on a path to be able to land from orbit. Starting with short hops by prototypes that get iteratively improved is the same methodology that allowed them to be able to land their currently operating Falcon 9.

They are the only one to ever achieve this. It's a big deal because everyone else builds a $100M rocket and then throws it away because it can't land. Reusable rockets have the potential to make açcess to space much cheaper.

dencodev
So the idea isn't to literally hop? They ultimately want to land it the same way the F9 rockets land now, and this is just a test?
dwaltrip
Yep, basically. The biggest difference is that this is the second stage. With this new rocket, both the first stage and second stage will be fully reusable. The Falcon 9 second stage is thrown away each launch.
badwolf
Bingo. They did similar tests with a Falcon 9 test article called "Grasshopper" - https://www.youtube.com/watch?v=9ZDkItO-0a4
deegles
It's basically the bare minimum to test that the components they're building work.
d_silin
It absolutely is :)
FactolSarin
It's basically the bottom part of their new Starship rocket
rwcarlsen
This is a prototype for the upper (second) stage of spacex's next-gen rocket [1] they are developing that uses their new full-flow staged combustion raptor engine [2]. This is the ship they plan to use for upcoming mars, moon, etc. missions that will basically replace all other spacex rockets as soon as they can figure out how to get it operating. This prototype is missing the nosecone, control surfaces, and other details, but has the most important parts - engines (one instead of 6 like it will eventually have) and fuel+oxidizer tanks.

[1] https://en.wikipedia.org/wiki/SpaceX_Starship

[2] https://en.wikipedia.org/wiki/Staged_combustion_cycle#Full-f...

app4soft
This is a prototype of the bottom part for the upper (second) stage of SpaceX's next-gen rocket — Starship.
m4rtink
While it does not look that way without the pointy nose cone, this is the prototype of the second stage.

The first stage will be a bit longer than this & its build enclosure is already being uilt.

garmaine
That’s what he said.
ninjamayo
This was incredible. I've been waiting to see this launch for months, especially after a few failures with previous versions. But it's all worth it. This is it! Next step will be even bigger and better. More hops, reigniting the engine and then 20km.
mosselman
I was just looking at the stream and what struck me is that people were donating to the channel... Why would you ever do this? $20, etc even.
Element_
Anyone here work on the flight control software? What's it written in? ada?

Curious how complex it is since it has to handle multiple engine failure scenarios etc...

mulcahey
I'd check out the sofware AMA they did a few months ago on /r/spacex

https://www.reddit.com/r/spacex/comments/gxb7j1/we_are_the_s...

fermienrico
Can someone please explain the significance of this milestone for a space-ignorant person like myself?

I thought SpaceX does these types of landings all the time. :)

rtsil
New rocket, new engines, new targets.

If Falcon 9 (the current rocket) was a motorboat capable of going from one port to a neighboring one on the same sea coast, this is the early prototype for a transatlantic liner.

It's designed to be much bigger, much faster and more powerful, while being fully reusable (like a plane) and extremely cost-effective, potentially 10 times cheaper than the Falcon 9, which is already the cheapest launch vehicle. That opens up all sorts of new possibilities.

And these hops are the first concrete steps toward that.

nieksand
SpaceX as a company is trying to solve the "transportation problem" of becoming a spacefaring civilization. Specifically, how do you reduce the cost of access by multiple orders of magnitude?

There are three big targets they need to hit:

1. Make Low Earth Orbit (LEO) cheap with a combination of launch cadence and reusability.

2. Reset the rocket equation in LEO by doing in-orbit fuel transfer.

3. Reset the rocket equation at Mars by generating fuel from the environment.

* The reasoning...

(1) A high launch cadence means you can switch from artisanal to mass production. You drastically reduce fixed costs of ground equipment and personnel. Experience translates to increased knowledge, reliability, and safety. You are less prone to schedule slip costs because there are more trains leaving the station.

(1) Reuse lets you get more life out of expensive components. It also helps you hit a higher launch cadence with less manufacturing capacity, further reducing costs.

(2) In orbit propellant transfer lets you start with a full tank again in LEO. It might take four tanker launches to refill one tank, but ultimately you can increase payload to non-LEO destinations by an order of magnitude. Being less mass constrained also makes things simpler and cheaper for payload development.

(3) Propellant production, aka in-situ resource utilization, lets you fully refuel at Mars or the moon. This lets you send non-trivial payloads in the return direction.

* The progress so far...

SpaceX has regular reuse of the 1st stage of their Falcon 9 and Falcon Heavy rockets. They have begun catching the fairings (nosecone) in giant nets mounted on ships and reusing those too. The 2nd stage is not reused. Doing so is difficult because it's much further downrange and has much larger velocity.

SpaceX has used their progress on reusability to drive down costs and capture a large part of the commercial launch market.

SpaceX is launching Starlink satellites to provide a global, low-latency, high-bandwidth internet access. Existing satellite internet is based on geosynchronous orbit satellites which have high-latency and low-bandwidth. SpaceX hoists 60 Starlink satellites per Falcon 9 launch. There are a couple hundred satellites in orbit already with several thousand planned. Their low orbit means they have a lifetime of just a few years and require regular replacement. If Starlink is a commercial success, then SpaceX will have found the "demand" needed to drive a high launch cadence.

* Why the SN-5 hop matters...

SN-5 is a prototype second stage for the "Starship" rocket. This rocket has both a massive payload capacity and _full_ reuse. In conjunction with Starlink this would solve (1). This prototype is demonstrating progress on the manufacturing process and viability of the design. There is still tons of work to be done.

SpaceX is already planning to do in-orbit propellant transfer using Starship, which then solves (2).

SpaceX has not begun on (3). However, the Mars 2020 rover mission actually has an experiment on board which does propellant production at demonstration-scale. The chemical reactions (sabatier process) are pretty straight forward, but providing sufficient energy and gathering the resources is a massive engineering challenge.

Ultimately, SpaceX has a coherent, achievable vision for reducing space transport costs by multiple orders of magnitudes and has made demonstratable progress towards that vision.

nieksand
An addendum to the "progress" section....

SpaceX has been flying cargo to the International Space System for some time using their Dragon capsule. A few days ago they completed their first manned mission on the Crew Dragon.

Three big items from this:

1. They have a reusable cargo/crew capsule for LEO operations.

2. They have gained experience in building human life support systems and associated ground operations.

3. They implemented autonomous docking for both the cargo and crew variants of Dragon. This is one of the keys to achieving in-orbit propellent transfer. Item (2) in my original post.

ianhorn
> 2. Reset the rocket equation in LEO by doing in-orbit fuel transfer.

What do you mean by this? If you want to propel a mass M to delta-v V, you need a certain amount of initial mass. Dividing it into stages is already taken into account. If you split the lower stages into multiple trips, you might change the mass per trip, but you don't change any of the total early-stage mass required, right? Doesn't the rocket equation still apply in exactly the usual way?

jecel
The total fuel required is the same in both cases, but to do it in a single trip the upper stage would have to be nearly twice as large and the lower stage exactly twice as large. This is already far larger than anything that has been done before, so making it twice the size would be a significant problem.
wonderwonder
Its a brand new rocket design. Massively bigger and designed to carry ~5x the weight. The entire thing is built to be reusable in the sense of a jumbo jet as opposed to a rocket. It should be able to carry ~100 people.

Good article: inverse.com/innovation/spacex-mars-city-stunning-video

smusamashah
Why is it shaped like this? Why the fire seems to be not exactly in center and how it managed to keep balance with that?
randallsquared
The fire is off center because they only installed one of the three engines that it would normally use, but didn't build a custom, centered engine mount.
db48x
It's a prototype of the lower half of a larger rocket, and it's not intended to fly very high or fast, so it doesn't need a nice nose-cone. The single rocket engine is mounted in the center, and it gimbals to the side to make the rocket move sideways. The on-board computer is balancing the whole rocket on that flame the whole time, adjusting it continuously to keep everything in balance and the rocket moving towards the landing zone; imagine balancing a pencil on your fingertip. The real rocket will have a lot more than just one engine, but for this test they only needed the one.
sidcool
The rate of innovation at SpaceX is mind blowing. There is little doubt they will achieve their Mars dream.
throwaway0a5e
If I were the CEO of Molson Coors I'd tweet Elon about buying advertising space right about now.
dgritsko
Did they already do it?
lpellis
Just did a minute ago, it worked! 6:57 in the the timestamp on the top right, I dont think I can link to a time in a live youtube video
ajaimk
Yes you can. FYI -> https://youtu.be/NJR4gZBLMNw?t=2190
lpellis
That 'copy video at current time' option wasnt available until the livestream ended though. I should have tried manually adding it.
dgritsko
Unbelievable! Congrats to SpaceX! Edit: just found this replay on Reddit - https://streamable.com/c2bff3
Jemm
"Norminal!"
jvanderbot
I cannot get over how it looks like an ork built this.
brianolson
skip to 36:20 for the action
monadic2
It’s times like these I turn to “Whitey On The Moon” by Gil Scott-Heron.
martythemaniak
I really love the out-in-the-open development process. It doesn't cost SpaceX anything, yet they attract lots of internet media where people set up streams, discuss progress etc. The next year should be pretty exciting as they develop things further. Starship has a number of big innovations, which are:

- the raptor engine. This was developed behind closed doors and is sort of finished. We won't see much of it, but it is the most advanced rocket engine ever made and I'm not aware of any upcoming engine that can compete with it.

- Stainless steel construction. What we're seeing with SN5 is the basic tank structure of the second stage. The hopper that flew last year was a neat demo, but SN5 was pressurized and the design is way closer to what the actual starship will end up having. The first stage tanks will also be a stretched version of these tanks, so that's why you see them focus on this so much right now.

- belly-flop landing. To land, starship will be coming downhorizontal until a few hundred meters above ground when it'll make itself vertical to land. SN5 won't have the fins and cone to perform this, but SN6 will. It might be possible to see this before the end of the year - SN6 (with 3 engines) goes up 20km, goes horizontal to burn off speed, then lands vertically.

- belly-first re-entry. Instead of a heatshielf that withstands a high temperature, Starship will burn off speed with its belly, but do it over a longer time period of time so that while the total heat is the same, the max temperature doesn't rise too much. The stainless steel can't take the temperatures ablative heatshields on capsules can. Don't know if Starhip will be able to perform this meaningfully without a booster.

- in-orbit refueling. Starship is big and heavy and basically can't get anywhere unless it's re-fueled in orbit. I don't think this has been done before, definitely gonna need 2+ starhips and boosters to show this.

- superheavy booster. This might be the simplest part of the whole system - a first stage with 31 raptor engines.

Lots of stuff coming in the next few years.

SEJeff
> - the raptor engine. This was developed behind closed doors and is sort of finished. We won't see much of it, but it is the most advanced rocket engine ever made and I'm not aware of any upcoming engine that can compete with it.

I believe the Raptor is the first actually working full flow staged combustion engine. It is sort of a holy-grail of engine for liquid rockets. Tim Dodd has a lot more info on it here:

https://everydayastronaut.com/raptor-engine/

However please call it what it really is. It isn't a belly flop so much as it is a skydiver maneuver. Just like how a skydiver splays out their arms and legs to maintain stability and slow down a bit, starship will do the same. Also like a skydiver, it will upright itself before landing as a belly flop would almost guarantee a RUD.

sandworm101
>> - in-orbit refueling. Starship is big and heavy and basically can't get anywhere unless it's re-fueled in orbit.

This is one of those "let's see" things that SpaceX has talked about but never actually explained. Their current rocket tech offers no hint as to how this is might happen. They aren't running internal bladders in their tanks. So the physical act of moving fuel from one tank to another is an open question.

The options are really limited. Either you use an internal bladder, something never done with cryogenic fuels, or some sort of maneuver to shift all the fuel over towards the pump. Maybe they plan on docking the two ships and then spinning the entire rig to create sufficient G to stabilize the fuel on one side of the tank? The entire operation seems more kerbal than reality atm.

skykooler
At the last presentation on Starship, Elon said they planned to do the refueling by applying a small amount of thrust during the procedure, giving a small g-force that's enough to drive the fuel from one ship to the other.
felixhandte
SpaceX did at one point describe using RCS to accelerate the paired vessels to facilitate fuel transfer [slide][video].

[slide] https://spaceflight101.com/spx/wp-content/uploads/sites/113/... [video] https://youtu.be/tdUX3ypDVwI?t=1411

balfirevic
Some rockets have already used small acceleration prior to engine ignition to settle the propellant in zero gravity situations: https://en.wikipedia.org/wiki/Ullage_motor
jvanderbot
Transfer tanks, not fuel. In-orbit servicing using robots, please. or just dock the tanks as vehicles.
krisoft
Sounds like a good idea. The problem is that for weight efficiency reasons in modern rockets the tank is the rocket. (So much so that they often crumble if you are not providing sufficient internal pressure.)
jvanderbot
I'd accept a future in which weight efficiency is slightly reduced to enable in-orbit refueling with standardized tank delivery. As others have noted, it seems extremely challenging without it.
Robotbeat
It's not particularly hard. Just like with regular rocket upper stages that require multiple burns to complete the mission, you can use small ullage thrusters to settle the propellant and make sure liquid (instead of pressurant gas) is transferred from one tank to another. The physics is exactly the same as making sure the engine receives fuel. Just need the thrusters to be fired longer.

SpaceX has done experiments with how much thrust is necessary for ensuring propellant settling. That's one reason you often see a video feed of inside the upper stage liquid oxygen tank during a Falcon 9 mission. It doesn't take much thrust to ensure propellant settling. Not at all an open question.

This always struck me as one of the least questionable new things in SpaceX's architecture. Much less Kerbal than most Mars architectures which require assembling a massive craft in LEO or whatever.

(One would be remiss to not mention the history of refueling... SpaceX's competitor ULA had been pushing refueling and orbital depots, which it called "distributed launch", since its formation, but has only been able to do small experiments since one of its parent companies, Boeing, sees orbital refueling as a threat to NASA's SLS rocket, which Boeing is the main contractor for. That's a huge reason for a lot of the "skepticism" about orbital refueling you sometimes see in aerospace circles, besides the usual pathologically conservative mindset of many grey beards...)

sandworm101
Yes but ullage thrusters would have to fire continuousky for the duration of the transfer. That is a significant burn time. If they are going to be draining the fuel using only the ullage thrust, it will take more than a slight nudge.
jcims
They would build a dedicated cargo section and fairing for this, all of that would be fairly straightforward to accommodate. I don’t know if SpaceX has acknowledged the idea but there was discussion of installing ’retro-rockets’ up in the fairing for the moon lander (to reduce exhaust blast on the regolith), could use the exact same technology.

If they were so inclined they cold even recover the helium from the tanks they are filling and use that to assist with pumping pressure.

BenjiWiebe
Wouldn't the thrust just be to settle the fuel so pumps could move it over?
hcknwscommenter
You need acceleration to settle the fuel and to keep it there. Once the acceleration stops, the fuel begins to unsettle.
krisoft
Usually when you ignite an engine on orbit a short kick of ullage trusters is enough. It is because once the fuel settled enough to start the engine the trust of the engine will keep the fuel settled. This is not true in the fuel transfer situation, there a single kick is not enough. If you are using ullage motors and not internal bladders, you have to keep producing the micro-trust for the whole transfer duration. Be mindfull that pumping a rocket-full of fuel won’t be an instantenous process.
Robotbeat
They would be using a pressure differential to transfer the fuel, not relying on just ullage thrust.

You'd be surprised at how low of an acceleration is required for propellant settling and transfer. On the order of 0.0001-0.01m/s^2. At a 310s Isp for the ullage thruster, that's between 0.01kg and 1kg of propellant usage per second. Even if it takes an hour to transfer fuel (on the ground, fuel is transfered in about 20 minutes and in flight, all the propellant is transfered from the tanks to the engines in ~8 minutes), we're only talking about maybe 1% of the propellant needing to be used for ullage thrust and perhaps as low as 0.01%.

ULA has published a paper on the topic: https://www.ulalaunch.com/docs/default-source/extended-durat...

rotexo
Out of curiosity, which of the engineering problems posed by the Starship/Superheavy system are the biggest potential showstoppers? My instinct is the belly flop/heat shield required to make Starship reusable, but I know nothing about rocketry.
dgritsko
> the most advanced rocket engine ever made

Would love to learn more about this, can you expand? What makes Raptor so unique?

martythemaniak
Tim Dodd explains it very well: https://everydayastronaut.com/raptor-engine/

It's basically a sweet-spot between being very powerful, very efficient, cheap and easy to operate and highly reusable. To get all these, they implemented a design that never got past the basic demo stage before, which included independently working out the secret sauce of the best Russian-made engine.

phkahler
>> which included independently working out the secret sauce of the best Russian-made engine.

Another hurdle was that there was no material available for some of the parts. SpaceX - so we'll get some materials science people to develop a new alloy that does what we need. Not an easy sub-task but one that needed a solution, so they found one.

bryanlarsen
There are two main metrics of rockets and rocket engines. Specific Impulse (ISP), and the Thrust to Weight Ratio (TWR).

ISP is essentially a measure of the fuel efficiency. And since there are no gas stations in space, the further you can go per kg of fuel, the further you can go, period.[1]

TWR is the measure of useful power.

TWR is the key measure for the first stage because a ton of power is required to escape Earth's gravity and atmosphere. For subsequent stages ISP is the main metric.

The Space Shuttle Main engines have an excellent ISP but because hydrogen needs massive tanks, it has a crappy TWR. Which is why the shuttle had a couple of strap on solids with a high TWR.

But instead of specialized engines, SpaceX designs engines that are good at everything. The ISP isn't as high as an advanced hydrogen engine and the TWR isn't as good as a solid, but both numbers are quite respectable and they bring other advantages such as the ability to relight and to be reused without refurbishment, they don't need use ablative cooling.

1: Although SpaceX is relying on in flight refueling for it's Moon and Mars plans. Nobody's done it before, but that doesn't stop SpaceX.

codeulike
Full flow staged combustion cycle, never been flown* before, explained here:

https://everydayastronaut.com/raptor-engine/

* The Russians built one in the 60s but it never got past static fire tests

paulsutter
In addition to being full-flow, Raptor runs on methane (CH4, the simplest hydrocarbon), which already exists many places in the solar system (including Mars), and is easier to manufacture than kerosene or liquid hydrogen.

SpaceX developed an incredibly advanced simulator to make it happen: https://www.youtube.com/watch?v=vYA0f6R5KAI

apendleton
Slight clarification: while there have been traces of methane detected on Mars, there's probably not enough to be able to easily use it as fuel. Methane is still beneficial for refueling on Mars, though, because you can make it in place out of water (which is plentiful on Mars as water ice) and CO2 (also plentiful, in the atmosphere) using the Sabatier process. So it remains the case that methane as fuel lets you avoid needing to bring enough fuel for a round trip.
SEJeff
Exactly. Elon has explicitly mentioned manufacturing metholox (the raptor engine fuel) using a really beefy ISRU factory. It would be feasible, but is still a lot of work required.
ba2plus
Mars could be the key to opening up the entire solar system. It's close enough to the sun for solar power to be practical, it's proven to have the mass amounts of subsurface ice and atmospheric CO2 needed for Sabatier-process methane/oxygen production, and it has a very shallow gravity well that would make it easy to lift huge propellant loads into orbit.

I don't think it's a stretch to imagine that Mars-based tankers supplying propellants and breathing oxygen would be commonplace through the solar system by the end of the century.

chriswarbo
The raptor is a "full flow staged combustion engine" https://en.wikipedia.org/wiki/Staged_combustion_cycle#Full-f...

AFAIK it's the only flying, non-research example of such an engine.

cplex_go_nogo
The raptor uses a full flow staged combustion cycle. This makes a very efficient engine but increase the complexity. Everyday astronaut and Scott Manly on youtube do an excellent job explaining this in more detail
Already__Taken
This might be the way to go - https://www.youtube.com/watch?v=Sdwy9fzQzl4
njarboe
I am not a rocket scientist, but one of the main reasons it is so unique is that it will be the first full-flow staged combustion rocket engines to successfully be used on rockets.

Rocket engines have powerful turbo pumps to move large amounts of fuel quickly to the combustion chamber to create thrust. Usually these pumps are powered by burning some of the propellant in a turbine and exhausting the resulting gas on the side of the engine. A full-flow engine mixes this turbo pump exhaust gas back into the main combustion chamber. This makes the engine more fuel efficient but it is a difficult engineering problem. All previous types of these engines blew up too often to be used on spacecraft. Check out the Wikipedia page for more info [1].

[1]https://en.wikipedia.org/wiki/SpaceX_Raptor

xcskier56
To add on, one of the biggest challenges with a full flow staged combustion engine is that the exhaust gas from the oxidizer rich turbopump is almost pure gaseous oxygen at very very high temperature. This combination likes to corrode and eat away any thing, metal included.

To solve this, SpaceX had to develop special metal alloys that could withstand this incredibly corrosive environment for long durations.

jcun4128
> 31 raptor engines

That'll be something to see haha N1

nine_k
Indeed, the N1 design [1] will finally be done right.

[1]: https://en.wikipedia.org/wiki/N1_(rocket)#Block_A_first_stag...

jcun4128
The Raptor engines are more advanced than those NK-31's right? I mean by newer manufacturing but I remember seeing something about these Russian engines that were closed off in some factory somewhere/later(years) found and they were supposedly still more advanced/powerful(efficient?) than modern rockets.
nickik
You are right and by some measures they were. However current engines like Raptor, BE-4 and in some ways Marlin, will be in many way more advanced.
nine_k
You likely meant his engine: https://en.wikipedia.org/wiki/RD-180

It wasn't used in the Soviet lunar program; these are remnants of the Soviet Space Shuttle-like program (specifically the Energia rocket that lifted the Buran space plane).

jcun4128
yeah that's possible those are the ones, I just remember seeing some documentary about finding these Russian rocket engines that were hidden away to protect them from being destroyed I think

edit: oh it's NK33/RD180 [0]

[0] https://www.youtube.com/watch?v=TMbl_ofF3AM

nkoren
The Falcon Heavy uses 27 engines and has a perfect track record ,so they've got some credibility here.
shdh
Just to add clarification, Falcon Heavy uses the Merlin engine, not the Raptor engine.
jcun4128
Yeah looks like 3 for 3 so far. It seems like a big number... as opposed to just 5 (Saturn V). What is the rationale for more smaller engines(other than offset/greater forces/new R&D)?
SEJeff
Why only turn it up to 11 when you can turn it up to 31? See the Starship dial goes all the way to 31.
HPsquared
Things have different scaling laws. Very large rocket engines might not be practical for a range of reasons: wall thickness required to contain the high pressures (this is probably a big one) combined with the temperatures, combustion instability, controllability, and general ability to manufacture. Why are elephants and ants differently shaped? Another example is piston engines: large ones generally have lots of (relatively small compared to the overall displacement) cylinders rather than a couple of massive ones.

If a small number of rocket engines was required they would probably have a completely different design, perhaps an aerospike. Or maybe resurrecting Project Orion?

SEJeff
I take it you've literally never seen this? https://www.youtube.com/watch?v=KOO5S4vxi0o

The joke went entirely over your head boss.

jcun4128
I never quite got the Orion(nuclear?) engine design eg. is it literal "nuclear explosions" or just using nuclear as a heat source.

I think they push fluid through the bells, maybe other materials(like ceramic) for the larger nozzles... can they use magnetic field to contain heat... probably not assumes it's ionized or something ha... heat still goes through magnetism. I got it, active heat destructive interface ha.

maccam94
Nuclear thermal rockets are much more interesting IMO because they were actually viable and in development until Nixon killed them for no good reason. They're coming back now though.

https://en.wikipedia.org/wiki/NERVA

https://spacenews.com/momentum-grows-for-nuclear-thermal-pro... (2019)

garmaine
Literal nuclear explosions, Every few seconds, with a giant spring to even out the force.
koalala
i suppose 2 could blow up, no problem :)
NikolaeVarius
Losing one means less affect on the overall mission
peter303
SpaceX using $3.6 billion investors money to build Starship.

It will probably circle the Moon before NASA SLS.

DannyB2
Lettuce not forget Raptor runs on Oxygen and Methane. Both of which might be produced on Mars.
fastball
I mean we know for a fact that there is already (in small amounts) methane and plenty of CO2 on Mars. Obviously if we find lots of H2O this all becomes even easier as we can just combine the abundant CO2 with the H2O to get loads of CH4 and O2.
anticensor
You mean, by unburning the fuel?
fastball
Yep, effectively! That is what is great about these fuels (H2 and CH4) vs something like RP-1. First you get hydrogen by electrolyzing water. Then you can go H2 + CO2 → CH4 via the Sabatier process[1].

[1] https://en.wikipedia.org/wiki/Sabatier_reaction

napier
> any upcoming engine that can compete with it.

There's the criminally underfunded SABRE engine, an a air-hydrogen mix breathing-rocket hybrid design from Reaction Engines that rated to reach speeds of Mach 25 (roughly 35,000 miles per hour).

As modelled, it's more efficient than any other current or proposed chemical propulsion technology, and the proposed single-stage runway launchable system would be capable of delivering around 11 tons of cargo to the ISS. The costs to go to orbit and beyond using this engine could be less than half that of current best in class technology; even less after development cost amortization. Not sure why SpaceX haven't invested in it yet. Perhaps it doesn't fit in with their current vertical integration philosophy, but it seems like a game changing technology.

nickik
SABRE engine is not really upcoming. It never even got close to production or prototype.

And the estimate cost of that vehicle were very optimistic with lots and lots of problems to overcome. A proposal like that from people who have never really done all that much is highly speculative.

The projected cost they could reach with that vehicle, is already beat by Falcon 9.

Elon Musk has even told the Royal Aeronautical Society that he thinks air-breathing engines are a bad idea. Massive complexity for not so much gain. Invest that money into better first stage engine, push threw the atmo quickly get out of it, and make optimal use of your second stage engine.

Its pretty save to say SpaceX will not invest in what is mostly a paper rocket with an engine that has only ever tested the cooling system.

nickhalfasleep
It's incredibly complex and has exceptional engineering challenges to make work.

That much cryogenic hydrogen and massive temperature differences is as the limit of engineering possibilities.

njarboe
SpaceX needs $kg to orbit to be much lower for their Mars plans to be possible. It is planning on their starship and superheavy rocket combo to bring down current launch costs by a factor of around 100 in the long term. A factor of two improvement in costs is not interesting to them.
Someone
Most of the time, you get an improvement by a factor of 100 not by two of a factor of 10, but by hundreds of a factor close to 1.

I think they would be very happy to get a factor of 2 in one step. It would only 7 such steps to get that factor of 100.

Having said that, they aren’t aiming for the most modern rocket technology as that implies “less well tested”, and will be less reliable. They’re building T-34s, not Tiger tanks.

FrojoS
Apart from the other reasons pointed out by others:

Single stage to orbit is sexy, but multiple stage to orbit is inherently more efficient and I see no reason why it Would be more expensive if you reuse all stages.

Yetanfou
SABRE might be an option for a first stage on vertically launched vehicle, to be used in that part of the atmosphere where the engine can get most - or even all - of its oxygen from the air.

Then again, if that stage were to be limited to a maximum height of ~20km it might as well be equipped with a stack of upgraded J58 engines (as uses in the SR-71), saving the weight of the cryogenic coolers used to produce LOX for those rocket engines. I guess SABRE makes more sense for a space plane than it does for a vertically launched rocket.

khuey
As I understand it one of the design goals of Raptor is to be usable on the Moon/Mars and I don't think the added complexity to achieve the air-breathing capability will be useful there.
mabbo
> Not sure why SpaceX haven't invested in it yet

> an a air-hydrogen mix breathing-rocket hybrid design

Tough to use a breathing rocket anywhere but Earth. And SpaceX's goal is to use this to land on the Moon, Mars, everywhere.

Ajedi32
That's true for Starship (the second stage) but AFAIK Super Heavy (the first stage) will only ever be used on Earth. Seems like an air-breathing rocket engine could potentially be good for that use-case.
shdh
Then you have to introduce another system (SABRE) and integrate it with your system instead of just using the same Raptor engines being used in the second stage vehicle.
simonh
Air breathing engines don't work well with the flight profile of vertical launch systems. Sabre wont develop near enough thrust to get a Super Heavy + Starship stack off the ground.
yazaddaruvala
One benefit of Raptor is that its designed to be mass produced. Achieving cost efficiencies with scale.

Adding another engine means, one more production line each with less production volume (i.e. less efficiency of scale).

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