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eterps
You made my day, awesome footage.
ars
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.

krastanov
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.
adimitrov
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/

ByThyGrace
Wow the "Timeline" section in the asteroidmission.org website is one gorgeous animated infographic. Thanks for the link!
evanb
There's also one with the fixed stars held... fixed.

https://twitter.com/landru79/status/988807933243863040

ars
Wow! A lot of what I assumed was dust was actually faint stars.
karlshea
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.
imh
Given how quickly the stars are moving, is the comet rotating quickly, or is it a timelapse?
bwang29
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

mark_edward
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.

tenaciousDaniel
JS is poorly understood in comparison

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

Tepix
In javascript:

x == x _ is true. Good.

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

And guess what:

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

But

NaN == NaN _ is false.

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

but then again

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

Madness, I tell you!

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bjoli
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".

conistonwater
Nitpick: NaN is supposed to work like that: the rule is that every comparison of any value against NaN returns false.
sixothree
At least x === x, right?
dak1
const x = NaN;

x === x; // false

bitwize
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."

Jesus_Jones
Those are impressive sounding achievements. I haven't heard of all of those, can you provide references or details about the stories?
adonovan
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.
soru
Has everyone given up on string theory, or is there still hope another few hundred genius-years will bring progress?
yetihehe
At least it's not erlang's string-list of integers duality.
dehef 

    Observable.of(rosetta)
         .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))
iliketosleep
Or just simply:

npm install rosetta-67P-rendezvous

aalleavitch
Then somehow get a completely incomprehensible error about Visual Studio executables.
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VikingCoder
Oops. The new probe smashed into Mars at 146 km per second.

It was a leftpad error.

mkirklions
>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...

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

z3t4
I guess relative to the stars in the image, using parallax.
ars
No, relative to the stars it's going a LOT faster than that!

Most likely it's relative to the sun.

knbknb
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.
Gravityloss
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.

Sharlin
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

orbital-decay
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.
amarant
damn! those are some gnarly slopes! any word on when spaceX will start doing ski-trips? ;)
bd
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:

https://streamable.com/w2wgj

https://streamable.com/dg3r0

(seems better quality than Twitter and YouTube)

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

https://twitter.com/landru79

BTW here are original ESA images:

https://imagearchives.esac.esa.int/index.php?/category/410/s...

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VikingCoder
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!

[dead] thejj100100
ESA, not NASA!

edit: or are you pointing out that NASA should do this?

pawelos
Rosetta was actually built and launched by ESA, not NASA :) Still, I couldn't agree more with your comment.
typon
What is that light on the left?
zaroth
Doesn’t look like anything to me.
nerdponx
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?
kerbalspacepro
The orbiter was 13km above the comet at the time these pics were taken.
onion-soup
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?

zeeveener
Every frame is 12 seconds, I believe.
mrb
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×

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

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

cpeterso
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. :)

yosyp
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.