[X] My Assistant

[Chmee]

Are there any working theories why the 2 impactor probes (Deep Space 2) that piggybacked on the Mars Polar Lander did not work? Their failure should have nothing to do with the problem with the MPL lander since they were released far above the surface.

I beleive they were designed to withstand 100 gravities of deceleration and still function. Anyone?

[Guest_BruceMoomaw_*]

The trouble is simply that -- as the failure report makes clear -- the things were so inadequately tested that there were three or four possible ways they might have failed WITHOUT even taking into account the possibility that they ran into some kind of freakishly hard, soft or sloping surface that would have wrecked them even if they hd been properly built.

[Bob Shaw]

I found an interesting image of the two Mars 96 Small Station landers in the .pdf of the NASA 1996 Mars Missions Press Kit. Interestingly, the document mentions that they would use airbag technology (just two big ones) and says (p52) that the same methods were used for the early Soviet Lunar landings in the 1960s! And on p54 there's mention of the twin penetrator probes returning data for a full year after landing...

...these may be just sloppy reporting on the part of NASA, however - unless there were RTGs involved somewhere along the line.

Bob Shaw

Attached thumbnail(s)

 

[helvick]

...these may be just sloppy reporting on the part of NASA, however - unless there were RTGs involved somewhere along the line.

Bob Shaw

Yep two small RTG's per landers - 86kg total mass, 12kg landed. Much more detail on this Mars 96 page
The small landers had 7kg of instruments:
Temperature, Pressure, Humidity, Optical Depth, Ion Anemometer, Alpha, Photon and X-Ray spectrometers, Magnetometer, vertical seismometer,, Panoramic Camera, Oxidation, experiment Descent Stage temperatur, pressure and accelerometers, Descent imager.

The two 45kg penetrators - powered by a single 0.4W RTG each had 4.5kg of instruments.
Camera, Temperature, pressure, Wind speed, humidity, Gamma Spectrometer, X-Ray spectrometer, Alpha Spectrometer, Neutron Spectrometer, Grunt Accelerometer, sub-surface thermoprobe, Seismometer, Magnetometer.

1 year planned surface lifetime for all four "landers".

Pretty compact - shame they ended up in the Indian Ocean.

[Bob Shaw]

Quite a lot of other detail at http://www.iki.rssi.ru/eng/index.htm - follow the links for interesting Venera etc images.

Bob Shaw

[Bob Shaw]

The IKI site is interesting - I hadn't realised that the Mars 96 landers were to be released before orbital insertion, but that the Penetrators would be released afterwards. The Russian Penetrators look considerably more thought-out than the American ones, gas-lighting or not!

Mars 96 images from http://www.iki.rssi.ru/mars96/08_mars_e.htm.

Bob Shaw

Attached thumbnail(s)