Waspie_Dwarf Posted September 26, 2014 #1 Share Posted September 26, 2014 Rosetta to deploy lander on 12 November 26 September 2014 The European Space Agency’s Rosetta mission will deploy its lander, Philae, to the surface of Comet 67P/Churyumov–Gerasimenko on 12 November.Philae’s landing site, currently known as Site J, is located on the smaller of the comet’s two ‘lobes’, with a backup site on the larger lobe. The sites were selected just six weeks after Rosetta arrived at the comet on 6 August, following its 10-year journey through the Solar System In that time, the Rosetta mission has been conducting an unprecedented scientific analysis of the comet, a remnant of the Solar System’s 4.6 billion-year history. The latest results from Rosetta will be presented on the occasion of the landing, during dedicated press briefings. Read more... 1 Link to comment Share on other sites More sharing options...
highdesert50 Posted September 27, 2014 #2 Share Posted September 27, 2014 A tremendous feat regardless of Philae's success. We have come a long way from Jules Verne's 1877 depiction, Off On a Comet. Link to comment Share on other sites More sharing options...
Merc14 Posted September 27, 2014 #3 Share Posted September 27, 2014 A tremendous feat regardless of Philae's success. We have come a long way from Jules Verne's 1877 depiction, Off On a Comet. It will be a tremendous feat especially since they had no idea, beyond an educated guess, about what 67P's mass, rotational period, shape or surface composition was. Link to comment Share on other sites More sharing options...
paperdyer Posted September 29, 2014 #4 Share Posted September 29, 2014 It will be a tremendous feat especially since they had no idea, beyond an educated guess, about what 67P's mass, rotational period, shape or surface composition was. So I guess either the probe will crash if the mass was under calculated by too much. Could the probe sink into the comet if the mass was over calculated too much? Link to comment Share on other sites More sharing options...
Waspie_Dwarf Posted September 29, 2014 Author #5 Share Posted September 29, 2014 (edited) So I guess either the probe will crash if the mass was under calculated by too much. That would be a possibility but there are likely to be large margins built in. Could the probe sink into the comet if the mass was over calculated too much? Why would it? It doesn't matter how low the density of the comet is, it's the composition of the surface that would determine whether the probe would sink in. A solid surface is a solid surface regardless. Besides, even if it did land on a deep layer of dust, the lower the mass of the comet the lower the surface gravity. The lower the surface gravity the less the probe weighs on the surface. The less the probe weighs on the surface the less the tendency to sink into the dust. All of these are moot points however. Since Rosetta is in orbit around 67P/Churyumov–Gerasimenko the simple application of Kepler's and Newton's laws will give an accurate figure for the mass of the comet. Since the comet's size is also known (by direct measurement from Rosetta) it's density and therefore surface gravity can also be calculated. There are many factors that could cause Philae to fail in it's attempt to land on 67P/Churyumov–Gerasimenko, not knowing the comet's mass isn't one of them. Edited September 29, 2014 by Waspie_Dwarf Link to comment Share on other sites More sharing options...
Merc14 Posted September 29, 2014 #6 Share Posted September 29, 2014 It will be a tremendous feat especially since they had no idea, beyond an educated guess, about what 67P's mass, rotational period, shape or surface composition was. So I guess either the probe will crash if the mass was under calculated by too much. Could the probe sink into the comet if the mass was over calculated too much? I should've been more clear. They didn't know any of the things I listed when they were designing Philae and it looks like they mad some pretty good educated guesses. They have much more knowledge now that they are in orbit but we'll have to wait and see how it works, as always. Weeks, months years of waiting and suddenly a couple of minutes of nail biting drama. Link to comment Share on other sites More sharing options...
Waspie_Dwarf Posted October 4, 2014 Author #7 Share Posted October 4, 2014 The comet is becoming more active. Jets are now clearly visible in the "neck" region of the comet. The latest image has been posted in the Asteroids and Comets section of UM Space Exploration gallery: Comet on 26 September – NavCam Link to comment Share on other sites More sharing options...
Waspie_Dwarf Posted October 6, 2014 Author #8 Share Posted October 6, 2014 Another newly released image of the comet, taken as Rosetta orbits lower and lower, preparing for the release of the Philae lander: Comet on 30 September – NavCam Link to comment Share on other sites More sharing options...
Waspie_Dwarf Posted October 8, 2014 Author #9 Share Posted October 8, 2014 Go for 10 km! With the last week spent at about 20 km from 67P/C-G, the decision has now been made to go to just 10 km.A series of manoeuvres will reduce Rosetta’s distance from its current 18.6 km orbit (taking 7 days) to an intermediate orbit approximately 18.6 x 9.8 km (with a period of about 5 days). From there the orbit will be circularised at about 9.8 km radius, with a period of approximately 66 hours on 15 October, and the mission will enter the “Close Observation Phase” (COP). This will provide even higher resolution images of the landing site in order to best prepare for Philae's challenging touch-down. Read more... 1 Link to comment Share on other sites More sharing options...
Waspie_Dwarf Posted October 8, 2014 Author #10 Share Posted October 8, 2014 Today's new image: Comet on 2 October – NavCam Link to comment Share on other sites More sharing options...
Merc14 Posted October 8, 2014 #11 Share Posted October 8, 2014 (edited) Today's new image: Comet on 2 October – NavCam You can see faint outgassing in the "saddle" area. I have been wondering if that is the main source of outgassing and hence the reason there is a saddle? Looking forward to the next few months as activity increases and some more answers. Edited October 8, 2014 by Merc14 Link to comment Share on other sites More sharing options...
bison Posted October 16, 2014 #12 Share Posted October 16, 2014 Here's an unusually picturesque image of comet 67P/ C-G. Taken from 30 Kilometers, but it looks much closer, somehow. This is the alternate landing site for Philae, if the primary site doesn't work out for some reason: http://www.esa.int/spaceinimages/Images/2014/10/philae_s_backup_landing_site_from_30_km_b Link to comment Share on other sites More sharing options...
Merc14 Posted October 16, 2014 #13 Share Posted October 16, 2014 Here's an unusually picturesque image of comet 67P/ C-G. Taken from 30 Kilometers, but it looks much closer, somehow. This is the alternate landing site for Philae, if the primary site doesn't work out for some reason: http://www.esa.int/s...te_from_30_km_b That is an amazing image. 67P is so different than what I imagined the surface of a comet to look like. Link to comment Share on other sites More sharing options...
bison Posted October 17, 2014 #14 Share Posted October 17, 2014 (edited) Yes, it's quite rocky looking. The surface seems to be largely free of ice. Surprising, given that this comet has not been coming near the Sun for very long at all, according to the dynamicists. Not many chances for the ice to have sublimed away. Some of the rocky-looking terrain contains an interesting texture. A criss-cross or lattice-like pattern has been repeatedly observed and commented upon. These linear features typically cross each other at right angles. This has been reported on the 'neck' area of the comet, but has also turned up elsewhere. I see that this has appeared again, in a NavCam image made on Oct. 15th. (Image linked below.) In the upper middle of the four-exposure composite image, a lattice-like pattern appears on a rough, dark cliff face. This lies just below a very light-colored, smooth appearing terrain, at the very top of the comet. The narrow black dividing line between the two upper images passes through the middle of the dark cliff face. http://www.esa.int/s..._October_NavCam Edited October 17, 2014 by bison Link to comment Share on other sites More sharing options...
Merc14 Posted October 17, 2014 #15 Share Posted October 17, 2014 Yes, it's quite rocky looking. The surface seems to be largely free of ice. Surprising, given that this comet has not been coming near the Sun for very long at all, according to the dynamicists. Not many chances for the ice to have sublimed away. Some of the rocky-looking terrain contains an interesting texture. A criss-cross or lattice-like pattern has been repeatedly observed and commented upon. These linear features typically cross each other at right angles. This has been reported on the 'neck' area of the comet, but has also turned up elsewhere. I see that this has appeared again, in a NavCam image made on Oct. 15th. (Image linked below.) In the upper middle of the four-exposure composite image, a lattice-like pattern appears on a rough, dark cliff face. This lies just below a very light-colored, smooth appearing terrain, at the very top of the comet. The narrow black dividing line between the two upper images passes through the middle of the dark cliff face. http://www.esa.int/s..._October_NavCam I see it now. Also at bottom left and right as well, although not as pronounced. Link to comment Share on other sites More sharing options...
bison Posted October 17, 2014 #16 Share Posted October 17, 2014 The 'lattice' in the lower right hand corner looks as if it's covered over, perhaps with dust. It appears to be a horizontal surface. Dust more likely there than on a vertical cliff face. Link to comment Share on other sites More sharing options...
Merc14 Posted November 3, 2014 #17 Share Posted November 3, 2014 (edited) A short video, designed to stir up interest in the mission, starring one of my favorite characters from The Game of Thrones TV series, Little Finger (Aidan Gillen), looking at the Rosetta mission from a futuristic, fantasy perspective. We're almost there folks! http://earthsky.org/...e0c1f-394012957 Edited November 3, 2014 by Merc14 Link to comment Share on other sites More sharing options...
Merc14 Posted November 12, 2014 #18 Share Posted November 12, 2014 Mission accomplished! Philae is on the surface and is transmitting data back to mission control. Link to comment Share on other sites More sharing options...
DONTEATUS Posted November 16, 2014 #19 Share Posted November 16, 2014 THis is a Great project ! The waiting part isnt though ! Link to comment Share on other sites More sharing options...
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