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A one-second video taken by the Rosetta probe on the surface of a comet (twitter.com/rainmaker1973)
526 points by mikecarlton on April 25, 2018 | hide | past | favorite | 81 comments

Unfortunately Twitter butchers video quality.

I remade both landru79's videos from scratch using original ESA 2048x2048 image sequence (plus I added a bit of motion interpolation):

http://alteredqualia.com/tmp/rosetta/rosetta.webm [50MB]

http://alteredqualia.com/tmp/rosetta/rosetta_stars.mp4 [28MB]


Edit: in case my server doesn't hold up, here are video mirrors on Streamable:



(seems better quality than Twitter and YouTube)

Dear NASA -

Science is amazing. Don't forget to make it relatable by doing work like this! People love to see great images, so you gotta curate them and highlight the stunning stuff like this!

Rosetta was actually built and launched by ESA, not NASA :) Still, I couldn't agree more with your comment.

Would love to see these without the frame interpolation (which totally chokes on all the particulate matter).

Here I made one for you, using just the original frames:

Video: http://alteredqualia.com/tmp/rosetta/rosetta.original.mp4 [15MB]

Mirror: https://streamable.com/l9x1o


Extra: I also attempted to denoise somehow (with Gimp's despeckle filter), though it's kinda weird :)



You're very talented, this is dope. Thanks for taking the time to make this and share it with us!

Credit should go to landru79, he keeps finding interesting things in Rosetta's raw data. I basically just tried to correct for Twitter's terrible video handling by re-tracing his steps :)

Go check landru79's Twitter feed, there are many more interesting comet images and videos (e.g. he combines multiple frames into color images):


BTW here are original ESA images:


Thanks for giving credit where it's due and your own work. I note that landru posted a GIF which is ironically much nicer than the video:


What is that light on the left?

Reflective flare from the sun, perhaps?

Doesn’t look like anything to me.

To put things in perspective, the comet, 67P/Churyumov-Gerasimenko, is about 4km in diameter, moving at 135,000kms per hour. Rosetta's rendezvousing with the comet required travelling a cumulative distance of over 6.4 billion kms. Gravity assists were needed from four planetary flybys – one of Mars (2007) and three of Earth (2005, 2007 and 2009) – a long circuitous trip that took ten years to complete.

Now back to my Javascript callback bugs

To be fair, people have been studying and predicting celestial movements for millennia, and boiled it down to unbelievably precise mechanical formulae. JS is poorly understood in comparison.

I say this to hope you feel better at work. I've been pressed into frontend web work and it's fractal complexity.

JS is poorly understood in comparison

This might be the most hilariously ridiculous true statement I've ever heard.

In javascript:

x == x _ is true. Good.

x == !x _ is also true. Oops?

And guess what:

Array(3)==",," _ is also true.


NaN == NaN _ is false.

Math.max()>Math.min() _ is also false!

but then again

Math.max()<Math.min() _ is true.

Madness, I tell you!

NaN not being equal to itself is true in all languages with IEEE compliance: https://en.wikipedia.org/wiki/NaN

Nitpick: NaN is supposed to work like that: the rule is that every comparison of any value against NaN returns false.

I just looked at the famous left-pad for the fastest way o implementing a pad function in JS.

I asked a friend that does web dev and it is apparently pretty idiomatic JS. Pretty appalling. I finally understood why people claimed it was "hard to get right".

At least x === x, right?

const x = NaN;

x === x; // false

But they're close to getting two numbers to add together!


They should use jQuery for that. I hear it's good for all the things.

Yes, but you're wading into the JavaScript weeds for what? More CRUD forms? Meanwhile...

"With a combination of large ground-based FORTRAN programs and small spacecraft-based assembly language programs, [Real Programmers] are able to do incredible feats of navigation and improvisation -- hitting ten-kilometer wide windows at Saturn after six years in space, repairing or bypassing damaged sensor platforms, radios, and batteries. Allegedly, one Real Programmer managed to tuck a pattern-matching program into a few hundred bytes of unused memory in a Voyager spacecraft that searched for, located, and photographed a new moon of Jupiter.

The current plan for the Galileo spacecraft is to use a gravity assist trajectory past Mars on the way to Jupiter. This trajectory passes within 80+/-3 kilometers of the surface of Mars. Nobody is going to trust a PASCAL program (or a PASCAL programmer) for navigation to these tolerances."

Those are impressive sounding achievements. I haven't heard of all of those, can you provide references or details about the stories?

I'd like to, but the original was from "Real Programmers Don't Use Pascal" by Ed Post: http://web.mit.edu/humor/Computers/real.programmers

You would be better off asking him about the veracity of the stories.

It's true. Some of the greatest minds have spent 20 fruitless years trying to discover a unified theory of object fields and elementary values in JavaScript.

Has everyone given up on string theory, or is there still hope another few hundred genius-years will bring progress?

At least it's not erlang's string-list of integers duality.

         .map(rocket => gravityAssist(rocket,'Earth'))
         .map(rocket => gravityAssist(rocket,'Mars'))
         .map(rocket => gravityAssist(rocket,'Earth'))
         .map(rocket => gravityAssist(rocket,'Earth'))
         .do(rocket => land(rocket))
         .do(rocket => tweetVideo())
         .catch(error => kaput(error))

Or just simply:

npm install rosetta-67P-rendezvous

Then somehow get a completely incomprehensible error about Visual Studio executables.

Use yarn

Oops. The new probe smashed into Mars at 146 km per second.

It was a leftpad error.

>Now back to my Javascript callback bugs

Check to make sure you are running the right files... Spelling/Capital letter errors... Returning after selecting a case...

Just some horror stories that cost me 8 days...

Moving at 135,000 km/h relative to what? (honest question)

I presume relative to the solar barycenter, and Wikipedia says that speed is its maximum speed (at perihelion of about 1.3 AU).

For reference, Earth does a mean speed of about 107,000 km/h relative to the solar system's center of mass.

I guess relative to the stars in the image, using parallax.

No, relative to the stars it's going a LOT faster than that!

Most likely it's relative to the sun.

There's also one with the fixed stars held... fixed.


And since massimo is a horrible disgusting freebooter who uploads degraded, double-encoded stuff he downloads from other people, there's also a clearer version of the OP video from the original creator themselves:


really they should replace the OP link with this.

Wow! A lot of what I assumed was dust was actually faint stars.


The HN title is wrong. This was not taken "on the surface", but from a 13-14 km orbit, according to source ESA data (click on a picture to see its data): https://imagearchives.esac.esa.int/index.php?/category/410/s...

Each picture is a 12.5-second exposure. Therefore this 25 fps video is sped up 312.5×

I was trying to figure out if the probe was sliding down a hill or if it was the camera panning.

14km and 312.5x speed up makes it quite surreal if not misleading.

Thank you! I couldn’t figure this out, as I thought the probe was shut down on impact. This makes much more sense.

It's really a shame Rosetta (edit: Philae not Rosetta) failed, because this video is unbelievable. I am seeing another world, which no one else has ever seen before.

Anyone know if there are plans to try again?

There's just something about video of another world, which simply collecting data doesn't approach, even if the data is more scientifically valuable.

I can't quite put it into words, it's like there's this other world where all this stuff is happening on it, and yet no one is there to notice it (so what's the point in anything happening there?), and it's just waiting for me (humankind) to come and see it.

Some people might feel insignificant because of that, but not me, quite the opposite, I feel huge, because it's waiting for me (us).

This has to be how people felt about the explorers of old. They must have been seriously famous.

Rosetta did not fail. Rosetta achieved all its goals, and then some. Philae's landing failed, but they actually got quite a fair amount of data from it, too.

This year, OSIRIS-REx is going to visit asteroid Bennu[0], and the exciting thing about it is that it's a sample return mission, i.e. the probe is going to head back & re-enter. RDV is in June/July, and touch down in December IIRC.

Probes visiting "other worlds" is kind of difficult, but it has been done, even in extreme cases, such as Venera (Venus) and Huygens (Titan) — if you don't know the pictures from these, you should really look them up.

[0] https://www.asteroidmission.org/

Wow the "Timeline" section in the asteroidmission.org website is one gorgeous animated infographic. Thanks for the link!

Rosetta did not fail, did it? The mission did include a lander that performed quite a bit short of expectations (it was operational only for a few days), but the Rosetta orbiter was active for a couple of years.

Original here, in better quality: https://twitter.com/landru79/status/988490703075463168

ESA PR is basically hopeless. It's the polar opposite of NASA. I guess the budget is nonexistent.

Good that there are people that disseminate these things on Twitter etc.

The Rosetta and Philae stuff, Emily Lakdawalla of Planetary Society did a better job of covering it than anyone at ESA, unfortunately.

To be fair, Emily Lakdawalla also did a better job covering the Cassini-Huygens mission than anyone at NASA. Her reporting about the Huygens RUSO/TUSO mishap and the overall mission coverage was top notch.

There aren't a whole lot of cases where Planetary Society aren't doing the better job. Two that come to mind for me are Marc Rayman's Dawn journal https://www.jpl.nasa.gov/blog/author/marc-rayman/ and HiRISE's outreach https://hirise.lpl.arizona.edu/

Yeah, it's bad. But at least their Rosetta stuff was way above their regular standards, with things like [1] and [2]. Of course those were more feelgood public outreach projects than technical reporting for space aficionados. But that's exactly what ESA needs more of, they simply don't have the sort of relationship with general European public that NASA has in the US.

[1] https://www.youtube.com/watch?v=PrctxlVWm_E

[2] https://www.youtube.com/watch?v=32vlOgN_3QQ

Isn't NASA prohibited from using any of its budget for explicit PR, to avoid anything remotely political?

(Honestly as a news consumer it's not all that bad because it means I can trust any communications coming from NASA proper to be purely mission oriented—focused on science.)

For anyone curious, there's a cute youtube series that the ESA made explaining what is rosetta, philae and what do they do. It's targeted for kids, but I loved it too.


This twitter user Massimo/Rainmaker1973 is constantly posting interesting content he finds on the internet, 7 days a week. Sometimes I wonder if it is actually not a single person but a small team of enthusiasts, scientists, experts and internet addicts.

That's just mind-blowing. I remember being really young when a comet came by and wondering what it would look like from the surface, and now here's an actual video.

This episode of BBC's The Sky at Night is a superb peek behind the scenes of the Rosetta mission: https://www.youtube.com/watch?v=nvGdoya8g4k

Again, what timeframe am I looking at here?

To truly grasp the awesomeness of this video I want to know is it 1 month of composite images or 1 to 1 video? Anyone?

Every frame is 12 seconds, I believe.

What is the scale of this scene? How tall is that wall?

I just finished reading Arthur C. Clarke's 2061 about people landing on Halley's Comet, so this video is a timely illustration of what they might have seen. :)

Confirmed: The stars in the background behind Comet #67P are in Canis Major: the cluster NGC2362 "falls down" past the limb at top-left; sparse cluster NGC2354 & the star 27CMa are also in the field.

Programming challenge: filter out (or otherwise remove) the sky from the video to isolate the comet surface for better analysis.

Given how quickly the stars are moving, is the comet rotating quickly, or is it a timelapse?

The comet was spinning with a period of about 12.4 hours, according to http://sci.esa.int/rosetta/58368-hu-keller-et-al-2016/ (so yeah, timelapse)

I believe you are seeing dust.

There is dust in the foreground and stars in the background. It's easy to distinguish because stars don't move relative to each other.

Someone posted it further up, but this stabilized gif really clarifies the difference well: https://twitter.com/landru79/status/988807933243863040

I don't understand the perspective here. Is this the orbiter looking "across" the comet, but "zoomed in" so it looks like we are standing on it?

The orbiter was 13km above the comet at the time these pics were taken.

Would love to see this with the stars and high energy particle hits edited out.

Anyone have an alternate link? Twitter is blocked where I am.

This is bananas.

You made my day, awesome footage.

This video is apparently not from the surface, but from several kilometers away:

>> Ross James Walker @rossjwalker96: Is rosetta moving on the surface here? Can't work out how the perspective seems to move to the right?

> Massimo @Rainmaker1973: It's moving, but these images were captured from 13 kilometres away. Rosetta flew even closer during its mission before landing on the surface in September 2016

damn! those are some gnarly slopes! any word on when spaceX will start doing ski-trips? ;)

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