[X] My Assistant

[vjkane]

Several of the presentations from the past MPEG meeting were posted recently

http://mepag.jpl.nasa.gov/reports/index.html

These include Draft priorities for Mars Sample Return, Mars Science Orbiter (MSO) Science Definition (nothing new, but a nice summary), and the Mars Strategic Science Assessment Group.

I found the latter document extremely interesting. It defines the rational for MSO as the mission to follow Scout 2013. It also defined 8 distinctive classes of deposits (of which Opportunity is exploring one) with emphasis that six have been identified in just the last three years showing that "we are still in an active phase of discovery". Understanding these deposits "are critical to understanding the history of water near Mars' surface." Ideally, it would seem to me, MSL and ExoMars would each explore a different type.

Most interesting for me, was the rational for a twenty year roadmap of exploration based on the assumption that sample return #1 begins at the end of the next decade:

2013: Mars Scout aeronomy
2016: MSO - determine presence and source of key trace gases, continue detailed monitoring of climate, continue to characterize surface with Hi-Rise class camera (and not mentioned, be available as a communications relay)
2018: MSR - lander/rover
2020: MSR - orbiter
2022: Mars network. Not chosen for 2016 in part to allow lessons learned from ExoMars geophysical station to be incorporated
2024: Mid-range rover (MER sized, but with updated instruments and tighter landing ellipse) - explore new class of deposit
2026: Scout
2028: MRS #2 orbiter
2030: MSR #2 lander/rover

Speculation: if budgets don't allow for a sample return in the 2018/20 opportunity, I wonder if the sequence of other missions would simply move forward, and perhaps a second mid-range rover would be added. Also, could these mid-range rover be powered by Sterling-engine plutonium systems?

[dvandorn]

I have a hard time defining MPF as a "rover mission." It was basically a technology demonstrator for the airbag landing technique, with a rover technology demonstrator.

Sojourner's science package was, to be honest, next to useless. Its cameras returned poor images with poor resolution, and its APXS took some great measurements of the dust on the outsides of some rocks (without a RAT or any other way of removing dust from the rocks, it never got a really decent look at the composition of the rocks themselves). The best science of the mission, IMHO, was done by the Imager for Mars Pathfinder (IMP) camera on the lander.

Not that MPF was a failure -- it just wasn't really a mission designed to land a rover and then do science with the rover. It was a mission to validate the airbag technique and to pioneer wheeled-vehicle operation at a Mars-to-Earth remove. It was an engineering mission, with a few science instruments added on to take advantage of anticipated engineering successes.

In purpose, it was rather like Surveyor I, which had all scientific instruments stripped off so it could serve as an engineering test. The only "science" payload on Surveyor I was its TV camera, which was used as much for engineering analysis of the Surveyor itself as it was for scientific analysis of the lunar surface. And looking at it, the only real science payload on MPF consisted of the IMP camera, the meteorology boom, and the APXS on the rover. The (rather deficient) wide-angle navigation cameras on the rover were designed solely for engineering/operational purposes; rather as with the MERs, these hazcam-like imagers weren't designed to do science, they were designed to help the operators drive the rover.

So, it's not like MPF and Sojourner were failures, it's just that it wasn't what I would call a "rover mission." The Mars 2001 lander wouldn't really have been a "rover mission," either, IMHO, even though it was scheduled to carry Sojourner's sister-toaster, er, rover, Marie Curie. It would have done more of its science from the lander than from the mini-rover, and once again would have been more like an engineering demonstration than a full-fledged rover ops mission.

-the other Doug