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First Flight of the Ingenuity Mars Helicopter: Live from Mission Control

NASA · Youtube · 546 HN points · 4 HN comments
HN Theater has aggregated all Hacker News stories and comments that mention NASA's video "First Flight of the Ingenuity Mars Helicopter: Live from Mission Control".
Youtube Summary
Up, up, and away! The Ingenuity #MarsHelicopter is set to make history. It will make the first attempt at powered flight on another planet on Monday, April 19. Don’t miss your chance to watch live with helicopter team in mission control beginning at 6:15 a.m. EDT (10:15 a.m. UTC) as they receive the data and find out if they were successful.
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Apr 19, 2021 · 546 points, 116 comments · submitted by hheikinh
Congrats to the whole Ingenuity team!

Exciting to see so many young faces and women on the team.

Also, I read up on the project lead MiMi Aung [1] - she's very insipring. I remember seeing her interview at the time when the rover was about to land, so much anticipation and hope. Now, so much excitement is truly uplifting.



From , the International Civil Aviation organization gave Ingenuity the the designator the aircraft type designator IGY, the call sign INGENUITY, and designated the Wright Brothers Field in Jezero Crater on mars as JZRO.

Hopefully that last one sticks when commercial service begins.

TIL: according the the Smithsonian Air and Space Museum, the copter is carrying a little piece of fabric from the Wright flyer:

The first letters (at least one, often but not always two) of any ICAO airport code represent the country it's in, and by convenient coincidence, the only three unused letters are I, J and X. I personally would probably have plumped for X as in extraterrestrial, but Xxxx codes are already frequently used for unofficial codes like train stations, so maybe someday Mars will indeed be J or JZ.

It made me so sad seeing them cheering and clapping, but not getting up and hugging each other :( So much happiness without the ability to vent it. Such a historical moment.
Funny. When I watched that sequence, I was thinking the opposite. That the length of the clapping and cheering would be "too much" for me. I imagined myself being in that room. I probably would have beed very happy, smiling and showing a "thumbs up" sign or something. But I would not clap or cheer. And I certainly would not want to be hugged by some scientist next to me :)

How do other engineers here on HN feel about it?

One year ago I'd have agreed.

Today? I'd be running around like an excited child, given half a chance. Probably hugging people I know are comfortable with it. I recognized I really do like that energy, and I only live once.

Not saying people who prefer a more restrained celebration are not valid in their preference! Everyone is a little different, and that is a good thing. At my workplace we like to have multiple ways to celebrate a milestone, because it's important that everyone can participate if they want. For example, we might have a team lunch/party (pre covid) for folks who like that, but also, say, personalized notes sent out, or office posters made of the achievement with participants' signatures on it (optional), and companywide announcements (again, representation optional).

For the record the only movie that routinely tears me up is Apollo 13. Specifically, when they land, and the people in Mission Control are shown. Some of those people have a lifelong bond because of that event, I'm sure. That's important to me.

There's no chance of me hugging the people I work with. None. Ever. I would only go for drinks with a few of them, but not often. Places vary, and in previous places I've had good drinking buddies, but hugging work people has never happened and never will. I'd hug the helicopter.
I do feel that cheering and clapping was a bit too much for me. If I was involved in something like this, I would have rather preferred a quiet moment of reflection.

Moreover such complex missions can go either way, I think it is perhaps better to be even-tempered and business like about it.

Extraordinary achievements call for extraordinary celebrations. I'd expected champagne bottles.
It's something that became pretty clear to me over the past year - if you don't get excited by this kind of physical contact you're probably a little different from others.

That's OK. I not only don't celebrate that way, it'd make me uncomfortable even for a peer I like to hug me out of excitement. It's not what I want but it's what other people want and it seems to be the norm.

You may end up learning that this may hold you back professionally at some point unless you can stay in a role that doesn't value social signaling, as these behaviors are basically expected, and not performing them will get you excluded, unless you find a way to surround yourself with people who have shared views on this sort of thing, which is really hard to find out because it's implied.

At least that's what I've been thinking this past year of isolation where I have been very happy to not feel obliged to do the social things everyone else so desperately wants to go out and do together.

I'm on the lookout for backcountry camping trips I can do once things are "back to normal" so I can continue my isolation while everyone is at restaurants and parties.

I don't think it's just cultural or anything for most people. Not just communication. I am usually not overly social at all, but I am now starting to crave other people's body warmth on a physical level. Feels like a headache... I can't enjoy anything anymore, because of it. The craving is there all the time, there is no substitute for the closeness I have not. I fantasize about pressing my body through an overcrowded club, collecting other people's sweat on me, friends screaming into my ears spitting all over my face. Sweat, sebum, saliva, warmth, smell, microbes, laughter, eye contact. It's not a sexual desire, it's something different completely drained, thirsty, essential for survival. I think back then, if my group abandoned me, I would just die of loneliness on the forest's mossy floor, no matter the circumstances.

I am gonna be really irresponsible, once I got my vaccine shot.

To be clear - I get it - I have had almost a hint of that sensation but I can see it clearly with all the people I work with - socialization will snap back hard and fast and people will go wild, good for them!
If I just got a helicopter up and running on another planet? I'd be hugging everybody.
No hugging but the joy in the room was palpable — even with masks you could see people literally laughing out loud when the altimeter data came in.
I agree, the one person who was excited looked like she stifled herself because the energy in the room was so low. Considering what they just achieved, and how much work they put into the project... I mean, we celebrate more when we have a successful sprint.
She did mention it, but they were probably told not to get too close for their COVID protocol. And watching her speech, she didn't seem stifled at all, she is so enthusiastic.

"We don't know from history what Wilbur and Orville did after their first successful flight, but I imagine the two brothers hugged each other. Well, you know I'm hugging you virtually. And, you guys who haven't been with me for 4, 5, 6 years...if it weren't for COVID-19 you guys don't have a chance of me (I think she was saying they wouldn't be able to stop her from hugging them) but I cannot give you a hug, so this is all I can do. I'm giving you the hugs."

> I imagine the two brothers hugged each other

Actually, that's pretty unlikely. It was a very different time. A display like that would have been considered unseemly. Also, neither Wilbur nor Orville were known for being particularly emotional or affectionate. Neither brother ever married.

Sadly relevent xkcd

The title text hit me a little harder than I was expecting:

> I've never been that big of a hug person, but it turns out I'm not quite this small of a hug person either.

> I've never been that big of a hug person...

The graph has a rough average of about 20 distinct people per year. Maybe I'm the odd one out here, but that seems quite high.

hugging is very risky @ work in US
You trying to get men fired?
It made me sad too.

All these brilliant minds working for so long and accomplishing so much... Just for a clap and cheer, yet tommorow they have to do it all again in the rat race. Yet cryptokings are basking in glory for a lifetime.

They didn't do it "for a clap and a cheer." They did it because they were inspired to add to humanity's millenia-long advance of scientific progress.

And I'd argue that cryptokings may be basking in money for a lifetime -- if they cash out at a good time and diversify their holdings. But the only people glorifying them are cryptoking-wannabes.

Different strokes for different folks, I guess.

I wouldn't worry about it too much. I've worked on a small dedicated hardware/software team with a multi-year focus overcoming challenging technical obstacles. We certainly weren't flying a helicopter on a remote planet, but the closeness and shared vision were similar. They know what they did and they know that they did it together. While hugging and other demonstrative behaviors are wonderful and should be cherished, they are trivial compared to the internal feelings of accomplishment and gratitude to have been a part of such of an effort with such a talented team. Those feelings and their shared bonds will stay with them forever.
Yay! Cool that they made it :)

The video feed had a "university team" feel to it that was sort of unexpected and nice :)

I was surprised to see the tack sharp shadow on the image from the downwards facing navigation camera. My thinking was that the rotors needed to spin way faster on this drone than on a drone on earth, because of how thin the atmosphere is on mars. But the sharpness seems to indicate that the rotor speed is perhaps all that different! Or perhaps the whole thing is just so light that there is not so much mass to lift up?

The Black and white bottom facing camera may have a very short exposure time and a global (not rolling) shutter.
The two rotor blades are just under 4 feet long, and spin in opposite directions at 2,500rpm. The rotor tips are moving at about 2/3 of the speed of sound on Mars. (For ref, Ingenuity weighed 4 pounds on Earth, so about 1.5 pounds in Martian gravity.)
Good data! Nice how martian gravity makes things lighter. If I'm doing the math correctly I get to to be an exposure time of around 0.1-0.5 ms. Fast!, but not unheard of fast :)
Yeah, lighter but an atmosphere so thin it's harder to get lift.

I wonderful aircraft if it is a net gain or loss — Mars vs. Earth.

Better quality video of the flight now on Youtube:
Why does the downlink operator have what appears to be Github open? He seems to be carefully monitoring it. Is raw data going straight to Github?
Seems like they are using a github issue to stream the data to, probably through a bot of some kind, I cannot find the issue where it is going on so I imagine it is on a private instance
Yes, if you look closely at their shell you'll see they are calling some `python3` command to get/push/(?) stuff into that PR.

Here it says "Enterprise".

Probably using the issue as an aggregation landing page. Bots can post to it, details can be manually added too, in-built support for media, integration with version control and ability to leverage in-built Github workflow. Looks like a smart way to use existing infrastructure.
I'm also curious to understand more about how Git comes into play here.
So he can file an issue if something goes wrong.
What a treat! A very slow and quiet drama, presented by a tight group, a team, of geeks. Appreciated by everyone watching. Looking forward to more.
There is a really good explanation of this machine on Veritasium:

Awesome! Well deserved congratulations all round to the team! Dare mighty things indeed.

Only negative thing I can think of is that I really hope the Perseverance rover has better video onboard just not transmitted yet. Maybe they will release it during the press conference later today. The one they showed was a little clipped. It had spin up. then it sort of cuts to the mid flight and then cuts to the spin down... all the takeoff and touchdown excitement is totally missing from the video they showed. If I didn't know as much as I do about how image telemetry is handled... I'd actually have thought it was broken, thats how abrupt the transition is in the video.

Yes, higher res, higher fps is coming, but will take a couple of days.

I hope the landing was smooth and we can look forward to lots of aerial photos from Ingenuity.

As I expected, I just didn't catch any mention of this during the Live stream, I figured I might have missed some mention of it since since I tuned in right about when they started getting data frames from the DSN.

I figured the team had decided to uplink only the most essential frames for this test flight (spin up, hover, and spin down) and send the low-res preview versions of them back in order to get the data back as fast as possible before a much slower upload of the full mastcam higher resolution video frames.

Whats extra amazing here is this is High Definition (possibly even in 3D) video sent to us from a nuclear powered rover on Mars!

I had to look it up because I could only see IGHTY THINGS, but the text on the wall is JPL's mantra, "DARE MIGHTY THINGS".


Or in this case, flighty things.
Well this changes the whole plot to The Martian if he can just get Domino's delivered.
Yeah, but the delivery fee is a doozy.
That's one small pepperoni for a man, one giant tip for mankind.
Might be cold by the time it gets there though
There’s a Korean food delivery commercial with just that theme:
This first successful flight on Mars is literally out of this world. Well done to all those involved.
It's cool. And surprising to me how young the team is. Contrast to the other videos I've seen of NASA "mission control" form the 60s etc.

Something transformational for me seeing this group of super young people achieve so much. Inspiring and hopeful and more :)

At various points they show people joining remotely via video chat. Perhaps the people in the control room self selected based on covid risk?
From the series, explanations of life in 2020-2024

Kind of sad, but valid point. Future historians seeing people wearing masks might think those kids were in the situation room for some biological attack apocalypse

The average age of mission control during the Apollo missions was around 26...
People looked older then, IMO. They smoked, had neat haircuts, and wore shirts and ties to work.
Owned a home, had 3 kids and were looking forward to their 10 year high school reunions.
Ouch. Right in the feels. Americana nostalgia, landscape of broken dreams song plays in background, fluro lights flicker on and off in the abandoned mall, an empty parking lot, Twinkies wrapper tumbling in the wind, somewhere static from the last analog TV purrs then switches off forever... Ask not for whom the generational bell tolls...

Second that about looked older... Maybe it was the super8 video quality

Is it too optimistic to hope that flights will keep the solar panels clean and Ingenuity could follow the rover some months.
Yes. They said that the Mars window is around 40 something days, and their schedule is around ~5, increasing in difficulty, flights. I suspect after that it will be tucked under the rover. But in meanwhile will be more videos so we have something to look for to in near future. History in the making nevertheless.
After that it will be abandoned.
> I suspect after that it will be tucked under the rover

There's no mechanism to reattach ingenuity to the rover.

Thermally, the helicopter cannot keep itself warm through winter due to decreasing solar power generation. Over the next few months, as the solar generation goes down leading into winter, the energy available for flight (rather than survival) will decrease and go negative at some point.
The universe is 13.8 billion years old. It took about 7.3 billion years for the Earth to be formed. Then it took roughly 4.48 billion years for the first Hominins to wander on the planet. They evolved for almost 5.998 million years. Then they had small civilizations in the past 0.002 million years. They started flying in the past 0.0001 million years. 0.00005 million years later they landed on the moon. Almost 0.00005 million years after that, the flew a machine over another planet.

Let that sink in.

I get your point, it's magnificent. But something seems off with those numbers:

7.3+4.48+5.998 > 13.8

You're mistaken: 5.998 million years not billion.
Oh man, you're right :+1:
Primates number one! Suck it fish and reptiles!
and then .00015 million years after they died out by the billions and reverted back to the stone age due to the pollution they emitted.
Pretty low faith that all that ingenuity will save us?
it certainly could if that genius was focused on the looming problem.

But instead of trying to prevent disaster, most of the world's ingenuity is squandered on trying to squeeze another buck out of the world.

The world is not as simple as you make it to be. SpaceX was founded by a guy who squeezed not one but many bucks out of the world. The same company just closed a funding round worth $1.2 billion from many investors who I'm sure are master at squeezing a buck or two. Yet they dream big and inspire a lot of young people to tackle hard problems. Turns out a squeezed buck today can go a long way to confront looming problems.
Wouldn't the sky crane be truthfully described as a "powered, controlled flight on another planet"?
Yesss... But they probably are only counting aerodynamic flight.

I wish there was more about what it did after it dropped its load. Did it just fly until fuel ran out? Or fly for a minute and shut off? I think they did say it crashed, which was probably unnecessary, considering how far away it got. It probably could have set down neatly 100 ft away.

Funny how there seems to be neither dust on landing or take-off.
It's probably a video issue, this preview video only has a few frames per second i'm guessing. As we see it pop up and then it's back on the ground
Beyond the video issue, I wonder if a bunch was already blown up during the test spins before the main flight.
It may have something to do with the fact that Mars' atmosphere is very, very thin (I think they mentioned it's 1% density of Earth's), so there are much fewer particles hitting the ground and pushing the dust, compared to e.g. a small hobby drone taking off here on Earth.

I'm sure there was some dust thrown up in the air, but probably not enough to be seen against the background.

Conversely, plenty of dust was blown around during the landing of the rover, but that was mostly from the rocket engines' exhausts.
So, so cool! Congrats to everyone involved!

I recently wrote a short piece about Ingenuity’s COTS hardware, its open source software, and its radiation mitigation techniques:

Event broadcast start time: 6:15 AM EDT. Programmed flight time: 3:30 AM EDT. More:
The engineering nerd factor is huge here and this is an amazing feat! Congrats to all involved.

I am curious what the importance of this is. What overall goal is this research contributing to? Is a mars landing system using "helicopter" style powered flight system the ultimate goal?

Cool! I wonder why balloons have not been used much on other planets? Is it the weight of the gas? The USSR had the the Vega 1 and 2 balloons on Venus, but presumably further missions could be pretty useful for studying planetary atmospheres, even for gas giants.
The gas has to be lighter than the atmosphere of the target planet. For planets with very thin atmospheres or planets with mostly-hydrogen atmospheres, that is hard to achieve. That leaves basically Venus and maybe Titan?
A clarification: technically, filling a balloon with a lighter gas is actually pretty easy: the pressure inside the balloon is almost the same as that outside (if the balloon is made of a non-stretchy material like mylar that doesn't compress the air), so all you need to have the inside be lighter is to use a less dense gas. Mars atmosphere is mostly CO2, so even nitrogen could work as a lifting gas.

The problem of course is that while it's easy to use a gas that's less dense than Mars' atmosphere, it can't be very much less dense because you're starting from a very low density. So, you'd need a huge volume in order to lift anything substantial.

edit: looks like a sibling comment said the same thing first..

Of course! Presumably you could use heated gases in the gas giants (like hot air balloons). I found this rather old JPL page which suggests it could be possible:
Actually, on Mars it's relatively easy to have a gas be lighter than the atmosphere; the atmosphere is mostly CO2, so most common gases, including nitrogen, are lighter than it. The problem is that since the air is very thin, you don't get much lift for a given volume. So for Mars you need a very big balloon, but it can be filled with almost anything.

(Side note: balloons have actually been used on Venus already, on the Vega missions!)

I don't think it's viable for Mars; the atmosphere there is only 1% of what the Earth's is, so (amateur armchair maths) to carry the same payload they'd need a balloon 100x as large, plus something to fill it with lighter than the surrounding atmosphere.
Keep in mind that the lifting power of a balloon scales with volume, not diameter - so something with 100x the volume is only about 4.6 times as big as the equivalent balloon on Earth.
Nature's write-up:
Countdown to when the take off is supposed to happen sorely missing.
It's already supposed to have happened, they are waiting for the data:

Interviewee stated turn around of about 4 hours; guess 7:30 EDT, i.e. prime morning show time.
A little video editing would be nice.

It's almost like NASA doesn't realize many people watch these videos.

I like watching behind the sceen stuff, but I also want NASA to come off in the best light.

The video had a production value of a subpar PBS late night video.

NASA has a duty to promote the agency too. There's a PR value to everything, especially when using public money.

(I want to give NASA more funds some days. Other days, I would rather give it to Musk. I'm not sure anymore who will use the money better.)

Would you rather want these funds to be spent on PR team and video editing or on missions?
I'd rather NASA had the funds for a little production value.

You can make the same whataboutist argument for why we shouldn't even be on Mars.

Relax a little, it literally just happened, better things are coming. And don't watch the live feed if what you want is a Hollywood production.
Estimated receipt of flight data is/was 6:15 EDT (10:15 UTC), which is what this livestream is for. The flight itself was scheduled to take place three hours prior at 3:30 EDT. As of this posting (roughly 6:30 EDT/10:30 UTC) they "are moments away from receiving" the data.
Edit around 6:55 EDT: Data received, confirmation of flight. They've got the video! Relevant spot in the stream:
I wonder if there's a public repository of the kernel source deployed on the helicopter. I'd love to see if any of the code I've contributed just flew on Mars
Check out this Github list of all repos included in the helicopter:
How long have they all been living on Martian time?

And how much longer will they have to stay on it?

Why are they all in prison?
Freedom means not caring what others think or do. Maybe it is you the one trapped in a confrontation prison.
This was painful to watch. The team can fly a drone on mars but apparently are so stupid not to realize there is zero science behind them wearing masks.
While I believe that masks do help reduce the spread of viruses, I'll play along that there is no science to back up that statement.

Humans do not only do things because they "make sense" / "scientifically proven", many times we just do it because its low effort and helps make other people feel comfortable.

Its like smiling when you see a stranger, or saying good morning to someone. There is no sense to it, you don't plan to stop and chat. However, it breeds a comfort (and eventually a distant camaraderie) because a greeting means a lot to them. Typically a greeting signals (sometimes falsely) a lack of malicious intent.

Given they are a team all sitting in the same room, even if one of them is more comfortable with masks on (logically or illogically), its just a kind thing to do for each other. Much like choosing to keep your cellphone off in a theatre, choosing not to smoke while in a group on non-smokers (outdoors or indoors), choosing to let everyone else exit an elevator before you, or choosing to respond to a comment you know is likely better left ignored :).

I wish you the best of luck in the future, and hope (masks or no masks - whatever strategy to help others you choose to use) you use some small amount of your time/effort to help make other people's lives a bit more comfortable.

"Don't feed egregious comments by replying; flag them instead."

Fair. I'll keep that in mind. Thank you for the link :)
"Eschew flamebait. Avoid unrelated controversies and generic tangents."

Everyone on that team looks really young.

These either age discrimination or people on that team use really good moisturizers.

I kid.

Kudos to the team for launching a flying rover on Mars!

Roughly the start of success from the livestream:

Video (of the video from Perseverance): (Better version from the livestream in child comment

I hope that in a little while we get an actual video like we got when the whole thing was descending onto the ground.

I am not expecting much from Ingenuity but I would be very disappointed if we didn’t see any video from Perseverance.

I know doing video requires a lot of power, but I really feel it is justified for something like this. It would become a historic video.

We'll get a full video once they have time to uplink it. Unsurprisingly, you can't stream high-quality video from Mars.
If I recall correctly, Perserverence was recording images at roughly 7hz and will be sending them back over the coming days. I don't think they are compressed as video, since perseverance has pretty wimpy main computers and isn't running FFmpeg like they had for the descent videos, which came from a separate system.
Can't wait until the SpaceX's Starship land the next gen Mars Helicopter that might be 10-20x bigger in 2-4 years.
Knowing spacex, they will deck that thing out with 4K video even if it means dropping a few satellites into Martian orbit to act as relays.

My understanding is that video requires power to transcode and compress, and power is a scarce resource.

This is especially true on ingenuity, which is powered by six 18650 batteries. And most of that power is dumped into just keeping it warm enough to function, not into actually flying.

Wouldn't transcoding the video still produce the same amount of heat?
Not that much as it will no doubt be hardware accelerated.
My point is that if you're spending electricity to generate heat, you can divert as much as you want to do calculations with no reduction in the amount of heat generated.
The problem I suspect is where the heat is going, heating up a logic board won’t do much to stop the motors freezing.
Battery-powered helicopter designs don't really scale on Mars any better than they do here on Earth. At higher vehicle masses, you'd need larger/heavier motors to get the larger/heavier blades turning as quickly as they'd need to (and in much lighter air than we have here).
Livestream timestamp of the video from Perseverance: (slightly better quality)
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