If this technique works out, it would very greatly reduce the cost not only of manned Mars ships, but of unmanned Mars sample-return vehicles in the near future -- and so MIP seems to me a much higher-priority item than MARIE and MECA. But the first package of MIP sensors weighs 8.5 kg, which I think is too heavy to be carried on Athena.

I wonder, though, about a longer-shot possibility. According to the April 14 "Space.com", the Jet Propulsion Laboratory is still seriously considering developing a "black box" for later Mars soft landers -- a very lightweight and shockproof recorder and transmitter package that could survive a crash on Mars and later radio back the engineering data recorded during the landing attempt, allowing the detailed post-mortem that couldn't be done on the Polar Lander.

I wonder whether such a lightweight transmitter could be added to the 2003 Pathfinder Lander along with the package of MIP experiments, so that they could transmit back data to Earth separately after the Athena rover had left the lander.

This first set of MIP experiments -- which would do such things as test the ability to manufacture small amounts of liquid oxygen out of Mars' carbon-dioxide air, and test techniques to keep solar cells clean from airblown Mars dust -- mostly has a very low data transmission rate, and could make use of such a system. This, however, is very speculative on my part.

Indeed -- as I said -- outsiders currently know very little about NASA's plans. Separate teams at JPL and Lockheed Martin are currently doing feasibility studies of both the Mobile Lander and the 2003 Orbiter, and NASA will make the decision as to whether to fly one of them -- or neither -- in July.

In the meantime, TerraDaily will continue to report on Mars developments with hopefully more advance information about the details of these two missions and the course that the U.S. Mars program will take after that.