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Unmanned Spaceflight.com _ Venus _ New Venus abstracts from two conferences
Posted by: BruceMoomaw Mar 6 2006, 04:26 AM
(1) Some more of the Powerpoint presentations from the Chapman Conference in February are now available: http://www.lpi.usra.edu/vexag/chapman_conf/presentations/index.html . (Perhaps the most interesting item is still page 14 of http://www.lpi.usra.edu/vexag/chapman_conf/presentations/mackwell.pdf , proposing that Magellan's temperature maps have found evidence of ongoing active volcanism in Devana Chasma.)
(2) The last of the available Chapman items, in turn, led me to the URL of a January Venus entry probe workshop by the ESA that I hadn't even been aware of ( http://www.aero.jussieu.fr/VEP/ ), which also contains some interesting stuff. Page 15 of the Balint presentation provides the name for Kevin Baines' new Discovery proposal, which I believe somebody was asking about earlier -- it's "VALOR" (Venus Atmospheric Long-duration Observatories for in-situ Research"), and apparently involves two separate cloud-level balloons instead of just the one mentioned by Baines before ( http://www.ims.demokritos.gr/IPPW-3/index_files/Book%20of%20abstracts.pdf , pg. 73). Note that space acronyms are getting more tortured than ever; this one compares to Calvin's "GROSS" club ("Get Rid Of Slimy girlS").
Posted by: JRehling Mar 6 2006, 10:02 AM
I looked at the map -- wow, that's a serious temperature gradient across that image; I'm surprised that such large gradients exist and would expect more than volcanism would be needed to account for it. Maybe topography is conflated with other things?
Posted by: BruceMoomaw Mar 6 2006, 10:27 PM
The only thing I could think of would be a peculiarity in local surface composition that increases microwave emissivity for the same temperature. It will be interesting to see what Venus Express' VIRTIS observes at this spot.
Posted by: edstrick Mar 7 2006, 08:23 AM
Microwave emissivity is generally quite high, I vaguely think around 85-90% percent. Very unusual and interesting are the radar-bright surfaces on Venus at high altitude (?10? km + elevation?) that have sharply lower emissivity. A number of 70% or a bit less comes to mind. These are currently interpreted as due to high-altitude concensation of metal-sulfide (or metal, like thallium!) at the comparatively cold temperatures at altitude. I'd have to dig to find what.
In general, sharply higher emissivity is unlikely or impossible cause it's normally high to start with. Sort of like trying to paint Enceladus white.
Posted by: ljk4-1 May 4 2006, 04:09 PM
Venus Entry Probe Workshop, ESA/ESTEC, 19-20 of January, 2006
Abstracts and Presentations online here:
http://www.aero.jussieu.fr/VEP/programme_final.html
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