Discussion
And even then the drill will, literally, only scratch the surface. The source of the gases and dust that make up the coma comes from deep within the comet - way beyond where Philae's little drill will reach.
Philae is just the start of our understanding of at least comet one out of millions.
Philae is just the start of our understanding of at least comet one out of millions.
One of the technicians explained on Radio 4 this morning why they have to shut Rosetta down just before it touches down -
the mission has ended so it is one of the rules of robotic probe space exploration that the transmitters be shut down once there is no more data to transmit. This is because the band of frequencies used by probes is very narrow and they don't want to clog up the airwaves and compromise the effectiveness of future missions
the mission will end automatically once they touch down because it is highly likely that, once Rosetta settles on the surface, it will sit at an angle that will stop its high gain antenna from pointing at the earth - which means that it could not communicate with earth.
This is why they have to send a signal to shut it down before it lands otherwise they will lose contact and miss the opportunity to send the "shut down" signal.
the mission has ended so it is one of the rules of robotic probe space exploration that the transmitters be shut down once there is no more data to transmit. This is because the band of frequencies used by probes is very narrow and they don't want to clog up the airwaves and compromise the effectiveness of future missions
the mission will end automatically once they touch down because it is highly likely that, once Rosetta settles on the surface, it will sit at an angle that will stop its high gain antenna from pointing at the earth - which means that it could not communicate with earth.
This is why they have to send a signal to shut it down before it lands otherwise they will lose contact and miss the opportunity to send the "shut down" signal.
ash73 said:
Makes good sense but they could easily program it to power down x days after touchdown, even without contact, rather than killing it on the way down.
They can't be sure that they maintain contact with the probe once it lands on the surface. The transmissions are spread over a very narrow beam angle so if the surface is not absolutely flat, the transmission dish will be resting at an angle and their is a high possibility that the beam will miss the earth - and transmissions from earth will not be able to reach the probe. The only cautious thing to do is to turn the craft off when they are 100% sure they can communicate with it. And that is what they have done.Halmyre said:
I can just imagine the project management discussions.
Chairman: "OK, it's time to discuss the final stage of the mission."
1st Engineer: "Let's leave it in space for eternity as a tribute to mankind's ingenuity and quest for scientific knowledge."
2nd Engineer: "Let's crash it into the comet!"
All Other Engineers: "YAAY! Crash!"
It's a very slow speed "crash". The impact will be at about 3 mph.Chairman: "OK, it's time to discuss the final stage of the mission."
1st Engineer: "Let's leave it in space for eternity as a tribute to mankind's ingenuity and quest for scientific knowledge."
2nd Engineer: "Let's crash it into the comet!"
All Other Engineers: "YAAY! Crash!"
Einion Yrth said:
It's on the surface of a comet that is now rapidly heading off towards the cold bits of the solar system; why does it matter whether it's turned off or not?
Its radio transmissions could interfere with future space probe transmissions.But its transmissions would be going to nobody as once on the surface, the transmitter dish is not aimed directly at earth - so it would be transmitting to no purpose.
It was considered best to shut it down.
I do think these people know what they are doing.
ash73 said:
Yes but you don't need to be in contact with it to switch it off, you can program it to switch itself off.
Rosetta's final image was a blurry mess
That's exactly how it was turned off. It was programmed to switch off at the moment it made contact with the surface. It's hundreds of millions of miles away. Because of the time lag in sending instructions to the craft, the only way to ensure it turned off was to programme in the instruction in advance.Rosetta's final image was a blurry mess
durbster said:
We clearly do not have the appropriate sophistication of language in astronomy yet. At the moment we're at the stage where we call everything that flies "a bird".
Meanwhile, I can't get past the idea that some other civilisation will discover Rosetta someday, and find two robots on it and spend eternity wondering what the bloody hell happened
Rosetta is the spacecraft. Philae is the lander. The comet is called - 67P/Churyumov-GerasimenkoMeanwhile, I can't get past the idea that some other civilisation will discover Rosetta someday, and find two robots on it and spend eternity wondering what the bloody hell happened
XM5ER said:
jammy-git said:
"We used to think meteorites were just big, barren chunks of rock and ice. Now through billions of dollars spend on space exploration and highly sensitive instruments that have been used to analyse the composition of many of these monoliths of deep space we can say that some are sticky, some are squishy and some are rather lumpy."
Love it.
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