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Posted by: RichforMars Jun 4 2015, 12:55 AM

Hi,

I'm curious to know, what does anyone here think?

I sure would like to another mission to that region, within range of the P&S mission.

Sojourner's last step was to be sent to fifty meters from the craft to analyis the rocks. So a hypothetical mission would look like one of the MER's or perhaps it may even be bigger to continue where the PS mission wasn't able to.

Obviously another Sojourner rover isn't practical for the terrain in that region, there wouldn't be anything wrong with another repeat of that mission, but as it is obvious missions are always innovative with testing technology.

Posted by: Phil Stooke Jun 4 2015, 02:22 AM

I don't think it's very likely. Our ideas about what is interesting on Mars have changed drastically since Viking and Pathfinder were sent to Ares Vallis.

The early landing site selection work was based on geomorphology - water was suggested by valleys, deltas, apparent crater lakes and so on. But all recent site selection is based very firmly on composition, looking for clays, chlorides, sulfates and carbonates (etc.) detected from orbit. There are clays around Chryse, targeted by ExoMars 2018, but not on the floors of the big valleys. So I wouldn't hold your breath.

Phil

Posted by: djellison Jun 4 2015, 05:05 AM

Yes there would. Why would you invest the money on sending the same spacecraft to the same place with the same instruments?

Posted by: RichforMars Jun 4 2015, 11:43 AM

To continue the work where the last mission wasn't able to ofcourse? Surely a probe like PS could be improved.

My impression is any part of Mars can be interesting, it just depends on what the mission objectives are.

It was more of an emotional thought than a logical one. Since the missions are fo far and few between, we are lucky enough to get any mission to that distant planet.

Posted by: MarsInMyLifetime Jun 4 2015, 12:57 PM

Check out the various discussions about NASA's Decadal Surveys, RichforMars. Because of that very scarcity of science-driven missions, each one must count for shedding new light on our knowledge of the solar system. The science community has its own list of burning questions that are periodically reassessed to come up with a strategy and recommendations for future missions. As two others have mentioned already, scientists learned enough about the Ares Vallis region to know that other scents on Mars are now more interesting. Did a big flood happen there at one time? Yes, but why? Trying to learn that story from the runoff debris is like trying to imagine what a cow is from looking at hamburger.

To get a better idea of how the potential for flooding could have existed for Ares Vallis and the many obvious water-made artifacts on Mars, you need to look for places that tell parts of that story. Places with layers are like pages of a book to geologists; layers reveal information about changes through time, and chemistry examinations can reveal what conditions were necessary for the observed changes. The missions for Spirit, Opportunity, and Curiosity were much better designed to answer questions about how water has worked over time, whereas Pathfinder/Sojourner found itself more like reconstructing an accident scene--a place where only one event and process is evident, where no layers exist that can tell new stories.

And thus, given both the exploration strategy represented by the Decadal Survey and the available budgets, and scale of time over which distant missions must be planned, and the workforce that has to be trained and mobilized to be ready for all aspects of the mission life cycle, and the opportunity to use latest knowledge to re-prioritize the goals of upcoming missions, we can expect NASA's upcoming missions to visit new regions that have those layers that bring order rather than chaos to the story of Mars.

Posted by: algorimancer Jun 4 2015, 01:15 PM

There seems to be an accelerated transition to smaller, but still capable spacecraft -- certainly in the cubesat realm. In 5-15 years it may be a relatively simple matter to scatter 20-30 or more small (perhaps hand-sized) rovers around all the dream locations of interest, including Ares Vallis (personally I'd like to target the bottom of Hellas as well as the putative delta regions bordering what seems to have been the northern ocean). This might take us into the realm of single-investigator spacecraft, and tolerance of failure, as opposed to the current flagship missions.