Chemcam, Laser Induced Remote Sensing Options

[Redstone]

Another interesting fact sheet on an MSL instrument. This one achieves remote sensing (up to 13 meters away) of elemental abundances by firing a laser and and performing spectrographic analysis of the resultant flash. Another part of the instrument is a Remote Micro Imager, which gives resolution approaching the MER MI, but at a range of 2 meters rather than 6 cm.

Apart from great opportunities for rapid science return, this instrument also has a significant coolness factor. I mean, a rover with a laser that zaps rocks! If that doesn't capture the public's imagination, I wonder what will?

Also: a new article on MSL and ChemCam from Astrobio.net. According to the article the Double and Delay option for MSL is still being considered. Anyone know when NASA will/must make a decision?

[cIclops]

Thanks for the links. Very clever ideas. ChemCam will enhance MSL's analytic power; it works fast and will enable preliminary analysis to help decide which targets to study in detail with Chemin etc. The RMI (Remote Micro Imager) will do the same for MAHLI (MArs Handlens Imager).

That zapper laser may also have other uses, it should be possible to detect it from orbit. Does the RMI use the same optics as the laser?

[Redstone]

Does the RMI use the same optics as the laser?

From the diagram at the top right on page 5 of the Fact sheet, it looks like they do. It looks like a beam-splitter or mirror directs the optical path, either from the laser or to the RMI or spectrographs through the telescope. I'm not sure if the laser is directed at the primary mirror of the telescope or if it shoots directly out of the tube.

[Gsnorgathon]

Does anyone else get a childish kick out of the notion of sending a nuclear-powered rover to Mars, equipped with a heat ray?

[Guest_BruceMoomaw_*]

The artist's renderings of the MSL firing its beam at various targets does bear an irresistible resemblance to "The War of the Worlds" in reverse (especially if they're all put together on one page, as I first saw them).

I've been meaning for some time to mention the existence of the very high-resolution black-and-white imager which is part of this instrument -- a very important addition to MSL's overall imaging capabilities. (Also, its three laser-flash spectrometers can be used in the passive mode as spot reflectance spectrometers -- which could be especially useful for long-range mineralogical analysis in the case of the longest-wavelength of the three spectrometers, which operates up past 1 micron.)

Also, two other points. First, this gadget can be combined with a Raman spectrometer that would use the laser's light to obtain long-range Raman spectra of its targets -- a very useful mineralogical technique which is also good at identifying organics. (Roger Wiens tells me that they came close to proposing to incorporate this capability into the MSL's ChemCam, but finally decided that it isn't quite well tested enough yet.)

Second, a ChemCam has real potential for future Venus landers, since one of the huge difficulties for the latter is carrying out surface-composition analyses quickly (before the lander overheats) and without having to utilize a complex airlock system to bring the sample inside (as the Soviets had to do for their Veneras and Vegas, and as the landers in Larry Esposito's "SAGE" proposal for the next New Frontiers mission would have to do). This gadget could obtain element analyses of spots all over the surrounding Venusian terrain in a split-second each, as opposed to hours for an X-ray or gamma-ray spectrometer -- and it is even more sensitive. One test has already been run showing that it could operate flawlessly for element analyses in the super-dense, super-hot CO2 air of Venus ( http://www.lpi.usra.edu/meetings/lpsc2004/pdf/1338.pdf ). And when I asked Wiens whether he thought it could also be used for long-range Raman mineralogical spectra on Venus (which I thought unlikely, since Raman- scattered light is extremely faint and I figured that Venus' dense air WOULD interfere with detecting that), he told me that he thinks it might even be usable for that, too. If it isn't, one could still have the lander deploy a simple movable arm, equipped with fiber optics, to bring the laser and the Raman spectrometer into immediate proximity with various spots on the surface so that Raman spectra could be obtained that way -- and the same arm could simultaneously be used for closeup color microscopy, near-IR reflectance spectra, and maybe even abrasion-wheel grinding of rock surfaces. (Near-IR surface spectra of Venusian samples also represent a problem, since the surface is so hot that it glows in the near-IR and this thermal-emission spectrum blends with and muddles the near-IR spectrum of sunlight simply reflected off the surface. The only way to separate the two is by changing the illumination conditions -- which could be done with that arm, and at longer ranges with a flashlamp or a broadbeam laser to provide separate spectra of various places on the landscape with and without the added illumination.)

Anyway, Laser-Induced Breakdown Spectroscopy (of which ChemCam is the first flight version) has a very bright future even if it doesn't finally make it onto MSL -- which it might not. At the first meeting of NASA's Mars Strategic Roadmap group which I attended, there was very considerable apprehension about whether it wil be possible to cram all 10 of the selected experiments onto MSL -- or even all of the highest-priority 6, of which ChemCam is one. And it was stated flatly that, if push comes to shove, ChemCam is lower-priority than the two instruments (SAM and CHEMS) which actually analyze samples that have been ingested and ground up by the rover.

[Guest_BruceMoomaw_*]

Correction: that other mineralogical instrument on MSL is CHEMIN, not CHEMS. (It's the combined X-ray spectrometer and diffractometer.)

[dvandorn]

Does anyone else get a childish kick out of the notion of sending a nuclear-powered rover to Mars, equipped with a heat ray?

That sort of pins down the landing site, doesn't it?

Now, where exactly on Mars *is* Grover's Mill, anyway...?



-the other Doug

[Guest_Sunspot_*]

Remote Micro-Imager
The RMI will provide very high resolution
images of targets. Its pixel field of view is
21-22 µrad, much finer than any remote
camera that has operated on Mars. Its
effective resolution exceeds that of MER
Pancam by a factor of 5 to 10. Resolution in
the near-field is within a factor of 2-3 of
MER MI (at closest-focus distance of 2 m for
RMI vs. 6 cm for MI), but still sufficient to
see many diagnostic sedimentary structures
and other features at the sub-millimeter
scale. Sub-meter-sized objects at the Mars
horizon will be visible.
NASA/

Sub-metre sized objects on the horizon?? WOW

Have any of the intruments to fly on MSL have been selected yet?

[cIclops]

<cut>

Have any of the intruments to fly on MSL have been selected yet?

Yep. Eight proposals were selected for phase A/B preliminary design studies last year plus three others, see http://www.jpl.nasa.gov/news/news.cfm?release=2004-290

[arccos]

>Double and Delay option
This is new information for me.
I would realy welcome sending two rovers instead of one, that would be great improvement fot this mission.
But if I shoul have decided, I would send one rover in 2009 and the second in 2011. Two reasons:
- we would get some data sooner (who wants to wait by 2011?)
- if the first rover fail, we would be able to improve/reconstruct the second rover to prevent another failure

[remcook]

a good article about MSL. makes me want the time to go faster

http://www.astrobio.net/news/modules.php?o...order=0&thold=0

[Marcel]

>Double and Delay option
This is new information for me.
I would realy welcome sending two rovers instead of one, that would be great improvement fot this mission.
But if I shoul have decided, I would send one rover in 2009 and the second in 2011. Two reasons:
- we would get some data sooner (who wants to wait by 2011?)
- if the first rover fail, we would be able to improve/reconstruct the second rover to prevent another failure

The double and delay option is under consideration for months now. I'd say that a winning recepy should not be changed: if they build two: just send them within the same window in 2011. It takes time: let MRO do the cartography, carefully select the landingssites (which also needs further thorough analyses of MER data) and incorporate the fanciest and most sophisticated instruments possible at that time. The results will be worth waiting for.....besides: i want them to show us multiple succesfull (completely) autonomous skycrane landings in rocky terrain on earth, before they send these babies !! The testing of this landing technology is going to take a lot of time and attention.

[Guest_BruceMoomaw_*]

There's another good reason not to launch both MSLs simultaneously -- the basic scientific purpose of repeat MSLs. Although this hasn't gotten as much publicity as it deserves, it was made clear to the Mars Strategic Roadmap Committee that MSL is actually yet another "reconaissance" mission of Mars -- its main purpose is to locate a place on Mars that has trace organic compounds, so that we can use the same spot as the site for the first Mars sample return mission. (Since the latter will cost several billion dollars a pop, we most definitely want to pick out the best possible scientific landing spot for it.) But if the first MSL fails to turn up organics, we would be up the creek when it comes to knowing where to send the sample-return mission (or even the possible cheaper alternative of an "Astrobiology Field Lab" rover carrying instruments for much more detailed in-situ analysis of the organics found by MSL) -- unless we fly another MSL (or even a third one, if necessary) that DOES locate such organics.

For the same reason, the science results from the first MSL are likely to be important in selecting the best landing site for the second MSL. The possibility can't even be ruled out that if the first MSL finds really promising organic evidence, we'll simply skip MSL-2 for now to save money and start focusing entirely on developing and flying the sample-return mission to the MSL-1 site as soon as possible. And if we do fly MSL-2, it may well not fly until 2013, to allow proper time in picking the best landing site (and instruments) for it. I keep quoting Gollum to describe the best Mars exploration strategy: "Cautious, my Precious! More haste less speed!"

[Marcel]

There's another good reason not to launch both MSLs simultaneously -- the basic scientific purpose of repeat MSLs.  Although this hasn't gotten as much publicity as it deserves, it was made clear to the Mars Strategic Roadmap Committee that MSL is actually yet another "reconaissance" mission of Mars -- its main purpose is to locate a place on Mars that has trace organic compounds, so that we can use the same spot as the site for the first Mars sample return mission.  (Since the latter will cost several billion dollars a pop, we most definitely want to pick out the best possible scientific landing spot for it.)  But if the first MSL fails to turn up organics, we would be up the creek when it comes to knowing where to send the sample-return mission (or even the possible cheaper alternative of an "Astrobiology Field Lab" rover carrying instruments for much more detailed in-situ analysis of the organics found by MSL) -- unless we fly another MSL (or even a third one, if necessary) that DOES locate such organics.

For the same reason, the science results from the first MSL are likely to be important in selecting the best landing site for the second MSL.  The possibility can't even be ruled out that if the first MSL finds really promising organic evidence, we'll simply skip MSL-2 for now to save money and start focusing entirely on developing and flying the sample-return mission to the MSL-1 site as soon as possible.  And if we do fly MSL-2, it may well not fly until 2013, to allow proper time in picking the best landing site (and instruments) for it.  I keep quoting Gollum to describe the best Mars exploration strategy: "Cautious, my Precious!  More haste less speed!"

To be honest, I don't understand how NOT finding any organics by the first MSL can improve the chance for MSL 2 to do so. In other words: if MSL 1 does not give us data that wants us to go there again to get samples to bring to earth, then what data can it provide us in order to let MSL 2 land on a location more likely to actually have organics ? Can you explain what you mend by "likely to be important in selecting the best landing site for the second "?

[djellison]

I suppose one good reason to do one MSL, and another in the following opportunity

If the first one augers in, the investigation board have about a year to make any change sugestions before the second enters ATLO

I still wish they'd find room for a netlander mission in the next 3 launch ops - it's ripe for an ESA/NASA colab like Huygens

Doug