Russia Plans "long-lived" Venus Probe Options

[Waspie_Dwarf]

Russia Plans "Long-Lived" Venus Probe

The press secretary of the Russian Federal Space Agency, Vyacheslav Davidenko, has said that Russia will design and launch a long-living probe to Venus by 2015. The probe is known as Venera-D.

Davidenko told a news briefing that within the federal Space budget for 2006-2015 was envisaged, “work to develop a principally new spacecraft, Venera D, intended for detailed studies of the atmosphere and surface of Venus”.

“It is expected that the craft with a long, more than one month period of active existence will land on the surface of the planet that is the nearest to the earth. Nobody has done such thing on Venus so far.”

Source: ITAR-TASS

[Guest_BruceMoomaw_*]

And here it is. One of the primary investigators on SAGE was Bruce fegley of Washington university (located, oddly, in St. Louis); and in 2003 he put a Powerpoint rpesentation on the Web regarding the desirable goals for such a Venus lander (keeping in mind that his own Venusian specialty is chemical interactions between the surface and atmosphere). That presentation no longer seems to be there -- but, once again, I recorded it at the time. It was nicely detailed, but here are what seem to me to be his most important spefications:

(1) The key atmspheric measurements include temperature and pressure profiles from the surface to the clouds. (Oddly, he says that not only did the Pioneer probes fail to get data below 12 km, but so, for some reason, did Vega 1 -- and since the 1970s Veneras were of questionable accuracy, Vega 2 sems to have provided us with our only good low-altitude T and P profile so far.) They also include composition, using a GCMS -- in order of priority:
Overall abundance of H2O, CO, SO2, N2 and the noble gases
Vertical profiles of the first three
COS, H2S, HCl and HF
Isotopic ratios for H, C, N, O, S and the noble gases
H2, H2SO4
CO2 abundance below the clouds

(2) The top priority surface analysis site should be a big representative region for average Venusian chemistry and mineralogy. Second priority is an anomalous region -- either a tessera ("some propose these are metamorphic"), or one of the high-altitude high radar-reflectivity regions. Both primary rocks and phases that have reacted with the atmosphere are needed -- preferably a depth profile using a drill core, and including if possible an examination of the atmospheric gases at different depths in it (here his own biases show).

The top-priority measurements are element and mineralogical composition together (elements by themselves are not worthwhile). The best mineralogical instrument is an X-ray diffractometer; element analyses should include elements from C through Na, which X-ray and gamma-ray spectrometry can't detect. Then, in order of priority, come:
Color imaging of the surface and the drill core
Fe oxidation state (he recommends Mossbauer for this)
Visible/IR reflection spectra
Oxygen fugacity in the surface (using a ceramic O2 sensor)

SAGE's payload, as indicated by the JPL description, doesn't include all Fegley's desired measurements, but it would include most of them.

[Guest_DonPMitchell_*]

Oddly, he says that not only did the Pioneer probes fail to get data below 12 km, but so, for some reason, did Vega 1 -- and since the 1970s Veneras were of questionable accuracy, Vega 2 sems to have provided us with our only good low-altitude T and P profile so far

Why does he think Venera-9 - 14 had questionable readings? Their platinum-wire thermometers are not as good as our platinum-wire thermometers?