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Posted by: Geographer Nov 8 2007, 04:21 PM

NASA's website has a vague description of an Astrobiology Field Laboratory launching around 2016, three years after ESA's rover. Would this use the philosophy of the Beagle 2, direct detection of organisms? Or would it be part of the future sample return mission, collecting interesting rocks?

Posted by: monitorlizard Nov 11 2007, 01:03 AM

I think the short answer is yes. It would be the next logical step after "follow the water" (MER) and "follow the carbon" (MSL). But if Phoenix finds no evidence of organic molecules and MSL finds no organics, then the fate of an Astrobiology Field Rover will be up in the air. It may be that a deep drilling mission would be the best chance of finding life or biomarkers if surface exploration finds nothing (and the 2-meter drill on ExoMars makes it and also finds nothing).

Alan Stern wants to fly a Mars sample return mission by 2020. It seems highly unlikely that the money could be found for a 2016 AFL and a 2020 MSR, unless there is a huge amount of international collaboration. If it could somehow be done, I think you would see a more sophisticated sample cache on AFL than the primitive add-on MSL will have.

Posted by: Mariner9 Nov 11 2007, 04:24 AM

When the latest round of MSR discussions came up a couple months back, one of the suggestions was to drop one of the Mars mission opportunities after 2011 in order to free up some extra cash for MSR. Initially it seemed like they were talking about either 2016 or 2018, since the 2013 orbiter would be needed for data relay.


But more recently I read somewhere that NASA headquarters (possibly Alan Stern himself, I don't recall) has asked people in the Mars exploration program that if they had to give up a mission, would it be the Science Orbiter?

Ballpark numbers, based on MRO and MSL, suggests they can free up 700 million from dropping MSO in 2013, or over 1.5 billion if they drop a lander project from 2016 or 2018. So a lot depends on how much money they need to save in order to afford MSR. (and assumes that MSR even happens.... this is a mission that has been studied every five years or so since the 1980s.)


So, what mission looks likely in 2016? That's a real tough one, since it's still unclear if there will even be a 2016 mission. But I would bet on at least one more rover mission before the MSR, so I think we'll see such a mission in 2016 or 2018.

Posted by: Eluchil Nov 11 2007, 07:45 AM

I suspect that AFL will be the next NASA lander after MSL. Unfortunately I fear that it will be either descoped or postponed into limited relevance. What I would like to see is the Mid-Rover concept instead (ie. two MER class rovers). This allows for the reconnaissance of more sites prior to MSR as well as requiring less development of new technology lowering cost and risk. NASA can't fly the series of next decade missions that it would like to and be ready to fly a MSR in 2020 without a level of international partnership (rather than participation) that it has not agreed to in unmanned spaceflight before. I.e. launch on an Ariane V and ESA eats the rocket costs.

Posted by: Geographer Nov 11 2007, 08:40 AM

Is another orbiter really necessary in 2011? How many new instruments could it have to make it worth it? MRO is returning 25 cm/pixel imagery, that should be good enough for any rover site-planning. A laser altimeter with more resolution than Global Surveyer would be useful.

Can MRO and Mars Express stay in orbit for another decade just to relay signals?

Posted by: nprev Nov 11 2007, 03:01 PM

One thing I don't like about the overall strategy is that it seems very discovery-dependent; almost looks like we have to strike gold with each mission in order to proceed to the next.

I hope that Alan's doing some good expectation management with the bean-counters & purse-string holders; Mars, after all, is a big place, and we can't expect to hit a home run every time.

With respect to orbiters, yeah, I think it would be wise to launch a new one every other opportunity or so just to maintain the relay infrastructure. Certainly most far outlive their design lifetimes, but you can't depend on that. In fact, I'd really love to see a rebirth of the Mars Telecommunications Orbiter with lasercomm for high-bandwidth throughput with a few science instruments added, of course.

Posted by: algorimancer Nov 11 2007, 03:03 PM

I'm inclined to think that another orbiter is not needed, and the most cost effective option would be an MSL2, with incremental improvements from lessons learned with MSL. Better yet, throw an MSL3 in there while you're at it. As long as they've got the hopper for collecting rocks as planned for MSL, they're laying the groundwork for MSR. I've yet to see any really persuasive argument for another orbiter other than to provide high bandwidth communications.

Posted by: nprev Nov 11 2007, 03:17 PM

I think that's pretty persuasive in its own right, though....plus the fact that you can add some instruments & do science as well. One interesting campaign might be monitoring the surface for long-term changes as MGS did with respect to impacts & the dark streaks; there are probably other things happening that we haven't noticed yet.

Perhaps the success of Kaguya & Chang'e will eventually get Japan & China into this mix. Most important thing is to fly standard UHF transceivers for surface probes on each mission in order to keep the link robust.

Posted by: vjkane Nov 11 2007, 04:24 PM

I agree. A sample return is likely to be a once in a professional career mission. Given that, you really, really want a good set of samples. Flying two (and I prefer 4 over two launch opportunities) mid-rovers allow them to take the time to pick and cache the best set of samples. You'd want a somewhat more robust set of instruments than MER, such as the addition of a Raman spectrometer to detect organics. Probably a drill similar to exo-Mars.

Posted by: vjkane Nov 11 2007, 04:28 PM

We do definitely need another Martian comsat -- MRO is designed to work only until Dec. 2010, and it would be dangerous to count confidently on its working longer. MSO, by contrast, will be designed from the start to work at least 10 years in Mars orbit.

Second, we badly need to obtain more engineering information on the Martian atmosphere -- both the wild fluctuations in its high-altitude density and (to the extent that we can obtain them) more data on its low-altitude winds. We are already perilously close to the edge of the extent to which we can land anything heavy on Mars with our current aerodynamic technology; our safety margin for such landings is now extremely thin. Something like a Martian weather satellite may now be almost as crucial as a Martian comsat.

Third: locating possible trace-gas sources may be an important new data input at this point in picking where to make future landings (as well as MSL's data).

The last two considerations, by the way, also make it pretty clear why NASA -- whenever it flies MSO -- has now decided to go with the "Plan A" mission in which the key instruments would be atmospheric (along with another high-res camera).

Posted by: Mariner9 Nov 11 2007, 07:45 PM

Am I the only person who has strong doubts about the whole Mid-Rover idea? I agree that there must be a middle ground between a full up AFL and the original MER, but I'm not so sure that you could do two Mid-Rovers for the price of a single AFL.

First problem, the Delta II is probably gone forever after about 2011. That means unless you have Falcon or some other commerically developed (and well proven) booster to replace it, you launch on an Atlas V or Delta IV, both of which cost a heck of a lot more than the Delta II that MER launched on.

Second problem: The airbag concept got stretched nearly to the breaking point when they scaled up from Pathfinder to MER. Europe thinks they can surmount this by going to a somewhat different airbag concept (I think they deflate on impact, acting like a big sponge or something). But even if there concept proves feasable, it means you are not just repeating the MER descent system.

Third problem: One of the big headaches in MER was the requirement to (1) survive the bounce, bounc, bounce of the airbag landing system and (2) be folded up into a much more compact envelope, to be unfolded and locked into final configuration upon landing. There is a big chance that if we go to a MidRover, airbag landing system, then those new rovers would have to be of the folding variety. Or they would have to re-use the sky-crane, which would be larger than what was needed (but might be cheaper than designing a new airbag system).

Fourth Problem: everything I have ever seen about the MidRover concept says that it is a larger rover than MER, but smaller than MSL. That means you are not building to any previous blueprints, but building an entirely new rover. One that would be too heavy to launch on the Delta II anyway, even if it were available.

Fifth problem: The Athena instrument suite, and much of the MER mobility system (rocker bar suspension) was based on over a decade of different study projects. One of the reasons they could jump into MER and launch in 3 years is that they really didn't start with a blank sheet of paper.

So.... with the Mid-Rovers I see a new rover, new descent system, new instrument package, launching on a more expensive booster than MER.

The AFL, on the other hand, could very likely use the same descent system, and rover, as MSL used. That right there helps keep it's cost contained (not a lot lower than MSL, but at least contained).

Given all of that, I really doubt you could fly two Mid-Rovers for the cost of one AFL. I would instead imagine that if the Mid-Rover concept ever comes into being, it will be a vastly downsized project to accomplish AFL goals, and only involve one rover.

Posted by: djellison Nov 11 2007, 07:54 PM

All I've seen is MER sized vehicles, with a few more KG of payload derived from savings in mass elsewhere.

Doug

Posted by: vjkane Nov 11 2007, 08:59 PM

I've seen the same, although I do recall a mention that some work was being done to study the concept. Whatever the form of the rover, though, I think it is essential to fly the sample collection/characterization mission prior to the MSR mission. This is clearly Stern's intention by putting sample caches on all rovers. Hower, the MSL samples are likely to be compromised by being ground, and the Exo-Mars mission may or may not include a cache. (I hope so.) If it does, I still think that a dedicated rover or two should be flown to find samples prior to MSR. The size and cost of said rover(s) TBD.

Posted by: nprev Nov 11 2007, 09:35 PM

MSR site selection should be most interesting, if all future rovers pack sample caches. Don't know how to weigh the relative importance of, say, phylliosilicates vs. sedimentary deposits...damn tough call, both tell different stories, and are unlikely to be convieniently co-located.

For painfully obvious budgetary reasons, MSR will almost certainly be a one-time good deal; we won't get a second chance. Gotta figure out how to maximize return in the best possible ways.

Posted by: Stephen Nov 12 2007, 04:44 AM

There was a 33-page description of the ASL in a recent issue of the Astrobiology journal. (The paper is free to download from the journal's website so anybody should be able to access it.)

The direct link to the paper is http://www.liebertonline.com/doi/pdfplus/10.1089/ast.2007.0153. (You'll need acrobat reader to view it.) If that link doesn't work, try http://www.liebertpub.com/publication.aspx?pub_id=99. That page has a link to the paper.

Among the mission goals listed (p3) are: "To search for evidence of past or present life by identifying the presence of potential biosignatures."

If you want more info there's a slightly older MS Word document (September 2006) about the ASL from a MEPAG committee http://mepag.jpl.nasa.gov/reports/AFL_SSG_WHITE_PAPER_v3.doc, while http://mepag.jpl.nasa.gov/Advanced_Mission_Studies/ has a link to a 2004 PowerPoint document titled "Astrobiology Field Laboratory - 2013 Biosignature Detection". (The "2013" is a reference to the outside chance, at least back then, that the ASL might conceivably fly in 2013. Dunno if that's still the case.)


The ASL is in competition with three other possible missions for the 2016 & 2018 slots, most of them landers. The ASL will probably get one of the slots, but if it's the 2018 one and the Mars Science Orbiter fliers in 2013 then the odds are such that it will probably NOT be the next lander after the MSL. (It may however be the next ROVER, since one rather doubts the twin mid-rover option will fly in 2016 if another rover, the ASL, is booked in for 2018.)

=====
Stephen

Posted by: centsworth_II Nov 12 2007, 05:41 PM

Yes! We need to pin down the elusive Martian methane!

Posted by: algorimancer Nov 12 2007, 06:03 PM

Good. I see that EDL and rover are derived from MSL - no point in reinventing the wheel again.

Posted by: Eluchil Nov 13 2007, 06:10 AM

There are a lot of possibilities (even assuming that some discovery or policy change doesn't redirect or scuttle the program). Still my feeling is that there isn't enough money for 2 flagship class missions in the two slots. Indeed, I doubt that they can even fund one and launch MSR in 2020. Therefore, I expect the other opportunity to go to a Scout which is likely to be an orbiter. Or it may be skipped entirely to provide funds for sample return (though in recent years NASA has been loathe to completely skip a Mars launch opportunity). On the other hand, my supposition should not be mistaken for certainty and I would be esspecially happy to see a lander network concept fly since seismic monitoring is the best (only?) way to study the deep interior of the planet.

Posted by: nprev Nov 13 2007, 12:12 PM

Heck, I'd be delighted just to see three fixed-site seismometers on the planet spaced 120 deg apart in longitude, combined with a camera & a methane-sniffer. I suspect that Mars is very quiescent because of its extremely thick crust, but think we need to do some quake monitoring to provide context for other observations (landslides, dark streaks, etc.)

Sounds like a Discovery-class effort, but I'm not sure if you could do it with one launch.