Philae landing on the nucleus of Comet 67P C-G Options

[katodomo]

horizon would be very very close I believe

More so because the CIVA-P cameras are mounted tilted 15 degrees downwards.

[vikingmars]

For those interested to attend this historic landing and take this opportunity to fly to Paris (and pay us a visit : TPS / UMSF Members, please, tell us in advance), here below is the link to the only other official ESA/CNES event set-up for the landing of Philae (with the one held in ESOC in Darmstadt).
As you may know, the engineering of the Philae lander is under the responsibility of CNES (the French Space Agency), as well as its CIVA cameras and instruments suite.

This event will take place at the National Science Museum (Cite des Sciences) in Paris :

http://www.cite-sciences.fr/fr/au-programm...-sur-la-comete/

...and thanks again for your kind support over all those nice comments and posts !
Enjoy !

PS : Societe Astronomique de France is the partner of TPS in France since 1982

[polaris]

Bonjour Olivier !

Faut-il s'inscrire ?
Même s'il faut attendre pour y participer, j'y serai !

Cdt

[vikingmars]

Bonjour Olivier ! Faut-il s'inscrire ?
Même s'il faut attendre pour y participer, j'y serai ! Cdt

Thanks a lot, Polaris
Please, try to arrive at 14:00 at the latest... And name you : I'll try to arrange so that you are well seated ! Friendly yours, VM

[mcgyver]

The idea of transmitting images during the descent has been considered before, even as far back as the Surveyor landings on the Moon, and including Phoenix on Mars (actually, Phoenix MARDI images were not to be transmitted live, just transferred into the flight computer, and even that was too much of a risk).
Every time it has been abandoned because of the number and complexity of other operations at the same time.

Why can't they just use a separated and standalone camera to take snapshots during landing? If it works, that's fine, else, who cares?

Is there a detailed 3d model of the landing site available for 3d printing? I already printed the comet model, but the landing site detailed 3d model would fit well close to it on my desktop. :-)

[djellison]

Why can't they just use a separated and standalone camera to take snapshots during landing? If it works, that's fine, else, who cares?

They do. The challenge is offloading the data thru the flight computer to be transmitted back up to Rosetta and from there on to Earth - all whilst the flight computer is trying to land.

[mcgyver]

They do. The challenge is offloading the data thru the flight computer to be transmitted back up to Rosetta and from there on to Earth - all whilst the flight computer is trying to land.

This remembers me of the infamous 1201 and 1202 alarms. Unfortunately there won't be any human onboard Philae, so actually delayed transmission is better!

Anyways it's really incredible to see how electronics evolved during mission journey!

[dvandorn]

As Curiosity demonstrated, though, it is quite possible (with modern electronics) to take descent images, store them and send them back to Earth later, when the landing sequence is *not* making the lander too busy to add the image transmission to its duties.

I would hope that planetary landers from now into the future will have this capability. It's not just valuable for developing context of the landing site within the general area, it also has the highest "cool factor" of any part of the missions, IMHO.

-the other Doug (With my shield, not yet upon it)

[mcgyver]

I would hope that planetary landers from now into the future will have this capability.

What I really hope/expect from future missions is HD video-shooting capability, rather than 1 Frame Per DAY "videos" ! Processor power and storage space are no more a mass/space issue, even if you'd enclose processor and RAM inside a lead box 3 mm thick! (Who cares if it will take years to send HD data back to earth? One day or the other they'll eventually arrive)

What was available on the (space) market in 1993 (date of mission acceptance) for onboard processing power and data storage? 10 MHz and 10 MB?

[djellison]

(Who cares if it will take years to send HD data back to earth? One day or the other they'll eventually arrive)

There's a few issues with what you're saying. Firstly - Rosetta is taking a lot lot more than 1 frame per day..... that's simply what's being released at the moment. Once all this data is delivered to ESA's PSA - there will be hundreds of image of 67P that people will be able to turn into pretty amazing animations.


And who cares how long it might take to downlink an HD video? Well actually - all the scientists and engineers entrusted with operating Rosetta and doing science with it. The amount of data it's possible to return from the somewhere as far as 67P is a massive constraint on operations. It's not a question of taking an HD camera, or processing it's data...it's getting it back to Earth.

A rough calculation: 90 second of highly compressed 720p video is around 170 Megabytes. At typical data rates from Rosetta - that would take 8 HOURS to download from the spacecraft. That represents pretty much an entire day's downlink from a typical deep space spacecraft. And for what? An HD video 90 seconds long that, to be honest, would be better represented by a few 2k x 2k still images anyway - and you would have given up all the other scientific measurements Rosetta could take that day. These spacecraft do not last for ever. It's wrong to assume data will somehow magically make it to Earth eventually.


Curiosity is capable of, and indeed has taken HD video from the surface of Mars - but only on a few very specific, very select and very rare occasions, for the same reasons - the quantity of data it's possible to return from deep space is a massive, massive constraint. Kaguya at lunar distances was capable of, and indeed did return many HD movies of the moon where the data rate doesn't represent such a constraint ( typical downlink from lunar orbit is more than 2,000 times faster than Rosetta right now.

[polaris]

Many thanks, Olivier !

I'll be there, right in time !

[Malmer]

I made a slopemap of site J using my terrain-model. (I'm assuming that the center of rotation is the gravityvector for the surface)



Cyan=good
Red=bad

[Malmer]

And an anaglyph of J using the same terrainmodel.

[SpaceScout]

Cyan=good
Red=bad

Great work! It looks promising for Philae. Can you tell us how much percent represent the "cyan=good" (<few degree) area?

[DDAVIS]

'An HD video 90 seconds long that, to be honest, would be better represented by a few 2k x 2k still images anyway'

There may well be dynamics that only video will show, something to keep in mind for a future comet probe. I think of water dumps from old live feeds on NASA TV.

'Curiosity is capable of, and indeed has taken HD video from the surface of Mars - but only on a few very specific, very select and very rare occasions, for the same reasons'

It seems a waste to have capability that isn't used.

I wonder what the minimum time between 'RGB' filtered frames is for Rosetta? If the interval is brief enough there should be color images of the comet. They can eventually be used to help add color to lander images.