tag:blogger.com,1999:blog-270899075443508100.post6611532378028924524..comments2024-01-03T20:28:17.727-08:00Comments on Future Planetary Exploration: Why a Comet Sample Return is So HardVan Kanehttp://www.blogger.com/profile/14227978868817989527noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-270899075443508100.post-90880690805872738172009-11-16T23:43:28.762-08:002009-11-16T23:43:28.762-08:00Interesting coincidence that you should write that...Interesting coincidence that you should write that -- today I ran across a reference to an early 2008 CSSR mission study carried out on NASA's orders by the Applied Physics Lab. The report itself, while it was supposed to be made publicly available, doesn't seem to be on the Web (I've asked Glen Fountain for a copy). But the Nov. 2007 OPAG meeting featured a presentation ( http://www.lpi.usra.edu/opag/nov_2007_meeting/presentations/cssr.pdf ) on how the study was developing (as well as an accompanying presentation on the mission's science goals: http://www.lpi.usra.edu/opag/nov_2007_meeting/presentations/cssr_science.pdf ).<br /> <br />It contains a great deal of interesting stuff, not only on the mission design but on the minimum that scientists are willing to settle for from it. Given your worries about the scientific worthwhileness of CSSR without cryogenic sample preservation, note in particular pages 14-17 (there are four pages on each PowerPoint slide) about mission goals, and pages 31-33 on sample handling. Trapping in flasks the gases from volatiles that vaporize at the sample storage temperature of minus 10 deg C. is important but not absolutely necessary. The same thing goes for collecting core samples (three of them) that are 50 cm long rather than just 10 cm. Eight or nine of the 11 Science Definition Team members thought the mission worthwhile without either of these, although they're both in the baseline design. Now add to this the enthusiasm for this mission shown in the poll of small-body scientists that you reported just three entries ago.<br /> <br />But there's the matter of cost: $820 million in FY 07 dollars according to the study (a "minimal" mission would cost $750 million), but that's presumably including the launch vehicle (which is not included in the $650 million cost cap for New Frontiers 3 proposals). I tried to look up LV costs and discovered that in 2004 the cost of a Medium Delta IV or a 400-class Atlas V was $140 million in FY 04 dollars, while a 500-class Atlas V cost $190 million. God knows how much they've gone up since then, or how inflation has affected all these costs. I've also asked Fountain for his opinion on whether CSSR could be flown within the $650 million NF 3 cost cap; all I can say at this point is that it looks very touch-and-go to me. If concern over those cost overruns that we're drearily familiar with is a guiding factor, I suspect we can write off CSSR for this opportunity.Bruce Moomawhttps://www.blogger.com/profile/11240647857073191582noreply@blogger.comtag:blogger.com,1999:blog-270899075443508100.post-65909054036829941712009-11-16T13:55:59.456-08:002009-11-16T13:55:59.456-08:00What's the point of posting those graphics whe...What's the point of posting those graphics when they're too small to even read?Anonymousnoreply@blogger.com