Rosetta Probe

[CrutyRammers]

croyde said:

Amazing colour photo taken from the orbiter.

Well, I didn't expect that!

[hornet]

ash73 said:

Of course it's a staggering achievement, that doesn't mean we can't learn from what went wrong. At the end of the day we do NOT have a repeatable landing system for comets, they need to go back to the drawing board and try again.

How do you propose we gather the data required to develop a robust comet landing system without first trying to land on a comet? There's only so much earthbound testing and simulation you can do, and even then many of the test conditions would be at best an educated guess. Would you have complained if the landing gear had worked, but the whole lander had sunk into a boggy surface and not been able to perform any experiments?

[hornet]

jammy_basturd said:

How do we know it has been undisturbed for 4 billion years? How do we know it's not even part of our own Moon - a piece that got chipped off by some collision a few decades ago?

Seriously?

[MarkK]

hornet said:

Seriously?

C'mon, do you not remember the great moon collision of '84?

[MartG]

Nimby said:

jammy_basturd said:

How do we know it has been undisturbed for 4 billion years? How do we know it's not even part of our own Moon - a piece that got chipped off by some collision a few decades ago?

From its orbit.

Tracking backwards its orbit would intersect that of the moon if that's where it came from - it doesn't

[jammy_basturd]

How do we know another collision hasn't changed it's original trajectory?

Whilst extreme, my point is that we've been observing this comet for what, a few decades? We have no idea of its history beyond that?

[CrutyRammers]

Well, it lasted until tonight at least. All of the experiments have been run, and sent back data. It's been rotated 35 degrees. But looks like that's it, battery nearly dead.

[MrCarPark]

Chris Lintott has been good to follow. https://twitter.com/chrislintott

Looks like Sky At Night are doing a special programme tomorrow evening, 9pm BBC4.

[130R]

Why was Philae not powered by a RTG? Was it a legitimate scientific reason or a stupid political one?

[MrCarPark]

130R said:

Why was Philae not powered by a RTG? Was it a legitimate scientific reason or a stupid political one?

That question was asked yesterday, and it's primarily political.

[Eric Mc]

Very few (relatively speaking) space probes are powered by nuclear isotopes. They tend to get used in circumstances where it is anticipated that the probe will not be getting enough sunlight to power the spacecraft and the experiments on board.

It was not expected that this lander would be short on sunlight - so solar panels made sense.

And, of course, there is always a risk in launching objects into space that contain these radioactive power sources and they only tend to get used when there is absolutely no alternative.

[hidetheelephants]

MrCarPark said:

130R said:

Why was Philae not powered by a RTG? Was it a legitimate scientific reason or a stupid political one?

That question was asked yesterday, and it's primarily political.

Most RTGs use Pu238, only the US and Russia has any appreciable amount of it and it's hard/expensive to make as it's not a byproduct of light water reactors. In the case of Philae I suspect the weight budget would not have allowed it anyway, as RTGs are bulky and heavy due to shielding requirements.

[Halmyre]

hidetheelephants said:

MrCarPark said:

130R said:

Why was Philae not powered by a RTG? Was it a legitimate scientific reason or a stupid political one?

That question was asked yesterday, and it's primarily political.

Most RTGs use Pu238, only the US and Russia has any appreciable amount of it and it's hard/expensive to make as it's not a byproduct of light water reactors. In the case of Philae I suspect the weight budget would not have allowed it anyway, as RTGs are bulky and heavy due to shielding requirements.

The weight of the thing was my first thought.

[FunkyNige]

Bit of a touching Twitter conversation between Philae and Rosetta last night

[davepoth]

It's probably only one person who does all of the ESA's tweeting, which makes that a bit disturbing.

Fingers crossed that they get a bit more light when the comet gets closer to the Sun.

[Eric Mc]

I think someone might be a fan of "2010".

Philae - "Will I dream?"

Rosetta - "Of course you will. All sentient beings dream".

[MrCarPark]

Halmyre said:

hidetheelephants said:

MrCarPark said:

130R said:

Why was Philae not powered by a RTG? Was it a legitimate scientific reason or a stupid political one?

That question was asked yesterday, and it's primarily political.

Most RTGs use Pu238, only the US and Russia has any appreciable amount of it and it's hard/expensive to make as it's not a byproduct of light water reactors. In the case of Philae I suspect the weight budget would not have allowed it anyway, as RTGs are bulky and heavy due to shielding requirements.

The weight of the thing was my first thought.

The answer is at 50 mins in this video: https://plus.google.com/events/c78o050l93ub7cm4kco...

Lots of other great Q&A in there too.

[Silver Smudger]

Astrophysicist Elizabeth Pearson - Philae is not dead it's just sleeping



Kidding aside, I am still seriously impressed by the mission so far.

[Mr Gear]

FunkyNige said:

Bit of a touching Twitter conversation between Philae and Rosetta last night

So on a serious note, there will still be plenty of good stuff coming back from Rosetta in the future?

[hidetheelephants]

Mr Gear said:

So on a serious note, there will still be plenty of good stuff coming back from Rosetta in the future?

I would think so, the plan on the wiki page has Rosetta following the comet until December next year, all the way round the sun and on the way out again. The ESA boffins mentioned stuff about the off gassing and the tail, so there's plenty of data still to be gathered.