Philae landing on the nucleus of Comet 67P C-G |
Philae landing on the nucleus of Comet 67P C-G |
Sep 23 2014, 12:16 PM
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Senior Member Group: Members Posts: 1084 Joined: 19-February 05 From: Close to Meudon Observatory in France Member No.: 172 |
Now, it's time to open a new section devoted to the landing of the Philae lander itself on the nucleus of Comet 67P C-G. Also to answer better the earlier post, http://www.unmannedspaceflight.com/index.p...st&p=212943 and for your information, here is the quick summary (as a "pdf" file) of the events that are expected to occur during landing on the nucleus and after : it's the timeschedule on which we are working to set up our EPO event in Paris. Sequence_ATTERRISSAGE10_UMSF.pdf ( 263.81K ) Number of downloads: 4544 The landing itself should occur around November 11th. We'll keep you informed |
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Oct 29 2014, 09:44 PM
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Founder Group: Chairman Posts: 14432 Joined: 8-February 04 Member No.: 1 |
It's not surface 'weight' that's the problem ( about 11 grams by my rough calculations - 0.01 Newtons )
It's the impact of landing. 1m/sec to a dead stop in, say, 20cm..... is a 5m/sec/sec deceleration - which is 500N of deceleration force for the 100kg Philae: 50,000x higher than the resting surface weight. |
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Nov 1 2014, 04:57 PM
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Member Group: Members Posts: 169 Joined: 17-March 06 Member No.: 709 |
I agree with Doug about the force of contact with the comet's surface.
It's not surface 'weight' that's the problem ( about 11 grams by my rough calculations - 0.01 Newtons ) It's the impact of landing. 1m/sec to a dead stop in, say, 20cm..... is a 5m/sec/sec deceleration - which is 500N of deceleration force for the 100kg Philae: 50,000x higher than the resting surface weight. In fact, I predict that the Philae lander will sink out of sight. In a paper by Schultz, et al, analyzing results of the Deep Impact mission, there is mention that the surface of Tempel 1 has a density of 0.2 - 0.5 g/cc, with a porosity of 90%! |
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Nov 1 2014, 05:59 PM
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#4
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Forum Contributor Group: Members Posts: 1372 Joined: 8-February 04 From: North East Florida, USA. Member No.: 11 |
...In fact, I predict that the Philae lander will sink out of sight. In a paper by Schultz, et al, analyzing results of the Deep Impact mission, there is mention that the surface of Tempel 1 has a density of 0.2 - 0.5 g/cc, with a porosity of 90%! Then how are house sized rocks sitting on the surface ? |
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