Second MSL Landing Site Workshop, October 23-25, 2007 Options

[Guest_AlexBlackwell_*]

SECOND LANDING SITE WORKSHOP FOR THE 2009 MARS SCIENCE LABORATORY
October 23-25, 2007
Pasadena, CA

Announcement (MS Word)
Information to Presenters (MS Word)

Note also the two August 2007 updates for MSL Landing Site Selection: User’s Guide to Engineering Constraints.

[Phil Stooke]

Here's the program for the second landing site workshop (Word file). It should be very interesting.

Phil

http://marsoweb.nas.nasa.gov/landingsites/...m_10_3_07_1.doc

[elakdawalla]

There's also a chart they're going to use to sort out the science possibilities and safety issues for each site.

I'm planning on attending at least some of this meeting, but am not sure if I'll be able to go to the whole thing...

--Emily

[algorimancer]

I don't suppose there's any chance that all the sessions will be recorded and made available for download somewhere on the web?

[elakdawalla]

I think it's safe to say there is absolutely zero chance of that.

--Emily

[ustrax]

Emily...this is a bit off topic but...here it goes...
That last post of yours at the blog is quite something!!!
I will NEVER be able to do produce taht fine quality back at spacEurope...
You will forever be a huge reference...Wow! I'm breathless...

[Phil Stooke]

algorimancer : " I don't suppose there's any chance that all the sessions will be recorded and made available for download somewhere on the web?"

elakdawalla : " I think it's safe to say there is absolutely zero chance of that."



I have to (sort of) disagree. Check out this link for the first workshop:

http://marsoweb.nas.nasa.gov/landingsites/...op/program.html

It's very likely that we will get exactly the same for the second. Not a recording, but the next best thing.

Phil

[ustrax]

Some space.com juicy stuff...
We're getting closer...

[ustrax]

Jean-Pierre Bibring (OMEGA's PI) will focus his presentation on three specific locations:
Mawrth Vallis, Nili Fossae and Meridiani.
He will try to convince the others that that geomorphological context is not sufficient enough for the choice of an MSL valuable site and that the choice must come also from additional mineralogical information (he gives emphasis to the phyllosilicates...).
I'll try to get something more from inside...

EDITED: Since I've invited Bibring to talk about what will he be doing at the workshop why not invite...everyone?
Thomson (Gale Crater) and Hynek (East Meridiani) already showed up at this "gimme you best Mars!" kind of party, let's see if someone else follows them...

[ustrax]

Horton Newsom is proposing a new site at the workshop and he has just e-mailed me a view of it...I especially like to imagine MSL roving along Adrian's Wall feature in the center...
The choice is going to be hard...

[ustrax]

I am not at Pasadena but my correspondant is...

Among other things he tells us the following, regarding the evaluations of yesterday's sites:

"Eberswalde and Holden came out on top (beating Nili/Jezero crater by a single yellow vs green on preservation of biosignatures).

Ritchey and Gale crater were rated lower (all yellows).

It is worth noting that Eberswalde and Holden may be faced with a challenge regarding the thermal issue discussed earlier; and from my perspective, it seems likely that Eberswalde will eventually get eliminated on the inability to place a viable ellipse inside the crater."

[monitorlizard]

The MEPAG site has added an interesting list of "Critical Data Products" for use in selecting the MSL landing site, at:

mepag.nasa.jpl.gov/cdp/index.html

These look like they should link to text and images, but don't. Hopefully, the links will be added soon, as MEPAG traditionally has open access to all of their reports, studies, etc.

[tim53]

There's also a chart they're going to use to sort out the science possibilities and safety issues for each site.

I'm planning on attending at least some of this meeting, but am not sure if I'll be able to go to the whole thing...

--Emily

Hi Emily!

Saw you here yesterday. Sorry I forgot to say "hi".

Are you here today? I could look around the room, I suppose. ;oD

-Tim.

[elakdawalla]

Hi Tim! Stayed home today -- I figured I could get the highlights of the site-by-site discussions from someone else -- but I'll be back Thursday to witness the bitter end.

--Emily

[tim53]

Thursday will be the most dramatic!

See you tomorrow.

-Tim.

[elakdawalla]

Presentations are being posted here:
http://hirise.seti.org/MSL_Landing_Sites/

At the outset of the meeting, the attendees were told that all presentations would be posted UNLESS speakers specifically requested that they not be. So you know who the "bad guys" are

EDIT: Here's a gem from the Watkins and Steltzner engineering constraints presentation (which is a monstrous 25 MB but is packed with interesting info): this image of the backshell was on a slide titled "We are big." No kidding.



--Emily

[ustrax]

The report from the second day of activities is already available at spacEurope.

Looks like there is the the possibility of MSL may be sending our regards to Opportunity personally...

"After the layered deposits session, the next talks looked specifically at the region around Meridiani/MER-B (generally because of the possibility for safely landing in this area of Mars. Of particular interest to the audience were sites around the margin of the MER Opportunity stratigraphic stack where evidence for phyllosilicates have been observed. Often the only /geomorphic/ evidence for water having been there are inverted features, however, which makes arguments for clear habitable context difficult. Nonetheless, the votes from the audience seem to suggest to me that at least one of the Meridiani sites is likely to get through ("East Meridiani")."

[Eluchil]

They are big! I just wanted to say thank you very much to Emily for her great coverage of the workshop. I find them fascinating. I remember back to the MER workshops and Nathalie Cabrol's presentation which one me over to Gusev as the best landing site. I can't wait to have a look at the MSL suggestions.

[nprev]

Not sure if I support a Meridiani revisit at this point. Given that we are slowly coming to the realization that Mars may have far more mineralogical complexity than previously thought, seems that MSL's range capability would be best utilized in an area that has as many boundaries between different mineralogical regions as we can find, combined with favorable EDL conditions.

Gotta admit that the possibilty of examing Martian clays is exciting, though; their very existence sets the mind to reeling!

[dvandorn]

In my humble opinion, the phyllosilicates are a number one priority. These clays seem to be the only things that preserve traces of a Mars which differs significantly from the current planet.

They may have been formed as early as at the very end of the LHB, but these clays were formed before sulphuric acids began pouring out of the interior and the entire outer surface of the planet was coated with sulphates. This is likely the only period in the history of Mars when conditions were truly favorable for life to develop, and as such are most interesting to me. (It has always seemed to me that we need to study extraterrestrial life before we can truly understand how life actually works. Until then, we're stuck behind assumptions that we can't see beyond.)

There seems to be precious little of this phyllosilicate material exposed on the surface. The question is, was there not much to begin with? Or was it more ubiquitous but now has been covered with lavas and/or coated with basaltic dust cemented together by sulphate salts? Investigations of the clays, and of the contact between them and the surrounding terrains, will go a long way towards painting a picture of very early conditions on Mars.

Now, if Meridiani shows significant clay exposures, I'd be all for landing there. We already know how benign the surface conditions are, and how likely it'll be that we can land MSL there safely. But the more we can place clay exposures into a geologically significant context, the more we learn. I'm not positive how much context we'll be able to derive in such a flat location -- you'd be almost totally dependent on entering medium- to large-sized craters to get your drill holes into the stratigraphy.

I'd rather find places we can land safely and then approach outcrops on cliff faces and hillsides. Seems a little more likely to show us context. Of course, I could be wrong...

-the other Doug

[ustrax]

Here are the final results from the workshop...the selected sites are...:

North:
Nili Fossae Trough
Mawrth
SW Meridiani/Clays
Jezero Crater

South:
Holden Crater
Terby Crater


In Purgatory...:
Eberswalde
NE Syrtis
Chloride Salts
E. Meridiani (Compelling Safe Haven)

[djellison]

No Gale That was my favorite.

[ustrax]

No Gale That was my favorite.

All of them were great but I'm very happy that the Nili Fossae Trough made it, and in my opinion, if the engineering constraints doesn't get to rough on it, it is where we'll see MSL making its way...

My precious!...

EDITED: Doug, Gale got a triple yellow...that was not a very brilliant result...
You can see the final classification here.

[nprev]

...this image of the backshell was on a slide titled "We are big." No kidding.

Good God! What sort of booster fairing diameter are we talking for this beast?

[djellison]

Same as NH iirc, but minus one booster. The 5m Atlas V fairing. (an Atlas V 541 for MSL - 5m fairing, 4 boosters, 1 engine upper stage)

Doug

[ustrax]

I have available the final report from spacEurope's correspondant at Pasadena...how on Mars was I so lucky to get this guy's precious, and (volunteer!) collaboration?!

[Stu]

Couple of colourised-strictly-for-fun-not-suggesting-they're-accurate-or-anything sections of that beautiful Nili Fossae Trough image ustrax, to thank you for your excellent work on this discussion for those of us anable to follow it so closely

[tglotch]

From my perspective, the workshop was a tremendous success. Narrowing more than 50 sites down to six was a sometimes painful process, but it was important for the scientific community to do that work so that the folks at the management level can focus on the most scientifically interesting places. The other option was that we give them a much longer list and the safest (and potentially most boring) place would be chosen because of engineering constraints.

A couple of interesting notes based on some previous comments: Each of the final six sites has exhibited the spectral signature of smectite clays in OMEGA or CRISM data (or both), although Nili Fossae Trough and Mawrth Vallis exhibit the deepest spectral features, which may correlate with abundance.

Holden and Terby came very close to not making the final list. They are both very interesting scientifically, but we were told by the engineers that because of their high southern latitudes and cold temperatures that if MSL landed at one of those sites it would have to lie dormant for the first month or so and then operate at only a 30-50% duty cycle. There was a lot of debate about whether the science that could be done at those sites outweighs those limitations. In the end it was a close vote, but both were kept on the final list.

The SW Meridiani site is very different from the MER B site at Meridiani Planum. It has been interpreted as a paleocrater lake and contains the spectral signature of smectite clays in visible/near-IR data. In addition, the TES and THEMIS data exhibit spectral character consistent with the presence of chloride salts.

[elakdawalla]

Tim, one thing I wasn't clear on at the workshop was what the time frame over which MSL would have the 30% to 50% duty cycle. At some times it seemed they were talking about lengthy hibernation (several months of inactivity), at other times it seemed they were talking about limited operations within a sol (needing to allow time for the rover to warm up, like a lizard in the sun as one person put it). Which one was it, or was it both?

--Emily

[ustrax]

Couple of colourised-strictly-for-fun-not-suggesting-they're-accurate-or-anything sections of that beautiful Nili Fossae Trough image ustrax, to thank you for your excellent work on this discussion for those of us anable to follow it so closely

You are welcome Stu, if it was stressful for me to manage all the incoming information I can't imagine what must have been for those guys at Pasadena...
My correspondent, Researcher X, must be a very happy and tired man by now, he has reasons for that...
There will be more next week...now it is time to have a rest and enjoy the weekend...

Just a request...mind if I use your images in a future occasion?...These can really drive your imagination...

[tglotch]

Tim, one thing I wasn't clear on at the workshop was what the time frame over which MSL would have the 30% to 50% duty cycle. At some times it seemed they were talking about lengthy hibernation (several months of inactivity), at other times it seemed they were talking about limited operations within a sol (needing to allow time for the rover to warm up, like a lizard in the sun as one person put it). Which one was it, or was it both?

--Emily

My understanding is that immediately upon landing at a one of the high southern latitude sites, the rover would enter hibernation and not do anything for a month or more. This is different than the situation of Spirit at Gusev, where although the rover was not moving during the winter, it was still acquiring imagery, APXS, Mini-TES, and MB data from its site.

Then, after hibernating for that extended period at the beginning of the mission, MSL would then be allowed operate on a reduced duty cycle.

[Stu]

Just a request...mind if I use your images in a future occasion?...These can really drive your imagination...

SUre, no prob; I'd be honoured to have my pics on spacEurope

[monitorlizard]

About MSL's hibernation, I thought waste heat from the rover's RTG was to be transferred to a circulating fluid that would keep MSL critical systems warm at all times. Is the temperature of the southern sites too low even for this heating system, or am I in error about having active heating onboard?

[dburt]

In my humble opinion, the phyllosilicates are a number one priority...They may have been formed as early as at the very end of the LHB, but these clays were formed before sulphuric acids began pouring out of the interior and the entire outer surface of the planet was coated with sulphates...There seems to be precious little of this phyllosilicate material exposed on the surface. The question is, was there not much to begin with? Or was it more ubiquitous but now has been covered with lavas and/or coated with basaltic dust cemented together by sulphate salts? Investigations of the clays, and of the contact between them and the surrounding terrains, will go a long way towards painting a picture of very early conditions on Mars.
-the other Doug

Other Doug - Great insights. Actually, the phyllosilicates may have formed as a RESULT of (that is, at the height of) the LHB - that period may well have been the warmest, wettest, most energy-rich time in martian history. (Remember, unequivocal signs of life appeared on Earth shortly after the end of its own LHB, other evidence of which has since been largely erased.) A life-hostile late episode of "sulfuric acids pouring out of the interior" is only one possible interpretation of the sulfate-rich surface of Mars, one that I consider rather unlikely. Others include weathering of igneous sulfides excavated by impacts (my "mine dump" modification of Roger Burns' gossan suggestion), and/or acid sulfate condensation/redistribution by impacts followed by the inability of frost or snow to leach these sulfates away from the surface (chlorides being much easier to leach, although some appear to have survived). The result was called sulfate duricrust back in Viking days and blamed on capillarity; effloresecent sulfate crusts on mine dumps form similarly. Later impacts (those occurring at the tail end of the LHB, after Mars had already seriously cooled down, or afterwards) may well have covered up many of the early clays (in addition to areas covered by late volcanism and wind). That at least is one interpretation of the impact deposits (if that's what they are) that appear to cover clay-rich sediments at both Meridiani and Gusev.

Phyllosilicates (clays) are excellent at absorping organic molecules, and I agree with you that fresh exposures of clays (as verified by CRISM and OMEGA) should therefore be priority number 1 for astrobiology (and for the MSL). I merely hypothesize that "very early conditions on Mars" (insofar as we can know them) were clearly dominated by impact cratering of the LHB, and much that we see today can still be attributed to that episode, either directly (e.g., craters and their distal deposits) or indirectly (e.g., impact-related ephemeral climate change; impact erosion of atmosphere). Whether or not life arose during those exciting times on Mars (as it may well have on Earth) remains to be determined. My personal favorite target for astrobiology might be rocks near the throat of a Tharsis volcano. Three billion years of near-constant heat, moisture, and chemical nutrients potentially could have provided a life-friendly environment impossible on Earth owing to plate tectonic movements. Of course, MSL is hardly going to land on top of a big volcano if it can help it.

-- HDP Don

[mcaplinger]

Is the temperature of the southern sites too low even for this [RTG] heating system, or am I in error about having active heating onboard?

Read page 28 and following in http://hirise.seti.org/MSL_Landing_Sites/W...s_Steltzner.pdf
The RTG heat only warms the interior; the instruments and actuators on the outside have to be warmed as needed by heaters.

[Borek]

Here are the final results from the workshop...the selected sites are...:
...
Jezero Crater
...

BTW, how's that Jezero Crater got its name? I ask because "Jezero" means "lake" in Czech.

-Borek

[Phil Stooke]

Jezero is also a town in Bosnia-Herzegovina, according to USGS. Probably named for a nearby lake.

Phil

[Phil Stooke]

There are new details and maps for the six current MSL site candidates:

http://marsoweb.nas.nasa.gov/landingsites/index.html

Phil

[PaulM]

My understanding is that immediately upon landing at a one of the high southern latitude sites, the rover would enter hibernation and not do anything for a month or more. This is different than the situation of Spirit at Gusev, where although the rover was not moving during the winter, it was still acquiring imagery, APXS, Mini-TES, and MB data from its site.

Then, after hibernating for that extended period at the beginning of the mission, MSL would then be allowed operate on a reduced duty cycle.

I think that the need to hibernate for one month or more rules out most Southern sites. My reason for saying this is that any probe sitting on Mars in the depths of Winter could fail at any time due to the expansion and contraction of solder joints.

One common thread running through MER briefings is that they concentrate on what Spirit and Opportunity will achieve in the next month or two. There seems to be a healthy acceptance that no rover can be presumed to carry on working for longer than a month or two in the very tough conditions on Mars.

[mcaplinger]

I think that the need to hibernate for one month or more rules out most Southern sites. My reason for saying this is that any probe sitting on Mars in the depths of Winter could fail at any time due to the expansion and contraction of solder joints.

Not a rover which is kept warm by a big lump of plutonium, though. External hardware is being designed to last for a minimum of one martian year of thermal cycles.

The hibernation may rule out southern sites because no one will want to hibernate that much, but it's not because of solder joint lifetime.

[edstrick]

My impression is that MSL is either less powered than originally concieved, uses more electricity than they expected, or something... We're getting "MSL Light" in a number of ways.

[Jim from NSF.com]

MSL has always had a 50% duty cycle. The RTG doesn't have enough power to permit constant roving. Anyways, roving in the dark is not a good thing to do and it would require more power than roving during the day. I haven't seen anything on a hibernation period at this point. I will make some inquires.