ChemCam to Determine Mars Habitability

Los Alamos National Laboratory (LANL) researcher Roger Wiens discusses the ChemCam instrument on the Curiosity Rover that occurred during a NASA press conference prior to launch of the Mars Science Laboratory. The ChemCam instrument was developed by LANL and the French Space Institute. ChemCam uses a laser to 'zap' features of the Martian landscape and then uses a spectrometer to gather information about the composition of the sample. ChemCam will help the Curiosity Rover determine whether Mars is or was habitable. The Rover is expected to touch down on Mars on August 5, 2012.

Transcript

00:00:01 created the rocks that we're going to be looking at and with that I'm going to hand it over to Roger wans who is the pi of the chem cam thank you Mike so uh to complement this Imaging Rover like curiosity also needs to get compositional information from a distance uh and so chem cam uh fulfills that role it will help guide the overover to the most interesting samples

00:00:25 uh in which the uh the analytical and contact and insitu struments can spend more time uh and be most efficient by by doing this with the most interesting in uh samples that we find at a distance so chem cam consists of two instruments that share the same telescope up on the Mast one is uh and let's go ahead and roll the the first video clip one is a laser induced breakdown spectrometer we

00:00:51 call it Libs Libs and the other is a remote microimager which provides context close-up images of the spots that we shoot with the laser so Libs has many advantages it uh can remove the dust From a Distance by multiple laser shots and it can also Analyze That dust but it can remove it and it analyze the rock that's underneath without being hindered by the

00:01:14 surface and so it's like an arm that can reach out up to 25 ft away brush something off analyze it actually look at the weathering surfaces and the interior of the Rock at the same time uh and uh so uh uh there are there are two main actually before I go on I'm going to I'm going to mention that the the instrument is a multinational uh collaboration between France and the US

00:01:40 and so half of the instrument was built in France and was contributed by the French space agency and the other half was built in the US so to represent the French part of it is uh in the audience is Dr Olivier Gano and you can address questions to him as well um so there are two main parts to the chem cam instrument correspond to the the French and us uh and so we're going to run the

00:02:04 next clip here and show you those first and then we'll give a little demonstration so here is the body unit this was built in Los Alamos in the US and you see a command and control unit at the bottom and then you see three spectrometers which actually do do the sensing for the the chem cam Libs this is the Mast unit shown here and this was contributed by France and it consists of

00:02:27 the laser the electronics for that laser and and a telescope with a four 4 and a half inch diameter and the camera that takes RMI images and what we're going to do here is we're going to show you a little demonstration of what Libs looks like in real life not in the animations so we're going to shoot at a pyite Target it's a mineral Target that's about 8 ft away and you're going to see

00:02:48 the libs flashes and you'll note that the laser beam itself is actually invisible uh but for the Sci-Fi Buffs we have to show it uh in the pictures um but there you see a still image of the lib's plasma so the the laser basically takes the energy of a million light bulbs and it and it focuses it onto a spot the size of a pin head and what that does is it ablates Material off of

00:03:12 that sample uh in an extremely hot State uh of thousands of degrees and when it comes off it's it's shining brighter than a flame and so what we do is we look at that light and we sense the composition of the samples that way so the next slide will actually show how that works uh so Libs really consists of two uh components or two two uh aspects the

00:03:37 first is the laser uh and that is the interrogating part so that sends the energy in to the sample and produces the plasma and in the second part of the spectrographs which we have to sense the light and tell us the composition and at the bottom of this image you'll see different color plasmas and that's actually how we see them with our eyes and so when we were running calibrations

00:03:59 we could uh we say oh this sample looks blue or that one looks a little different color and the other thing that you notice from this is that these are relatively large plasmas uh and that's the case on Mars in fact with the Mars atmosphere you get a bigger and brighter plasma than you do it in these pictures that I just showed in the video on Earth U and so I hope my colleague Mike will

00:04:20 get us some good pictures of our of our plasmas there um but now I'll show you how chem cam gives uh the the the sensing part of that with the next image so this is this is the spectral range from one of our three spectrometers that sits in the body of the Rover and by the way the light comes down from that telescope down along the Mast and into the body of the Rover along a 20 foot

00:04:43 long optical fiber and then it gets into the body and it's sensed like this and so the spectrometers actually spread out the light along their along the wavelengths and then you see these uh emission lines and the emission lines uh represent different elements and they're they're labeled there for this spectral range and you can see that some of the elements have many emission lines some

00:05:05 have only a few but we spec our instrument to cover essentially the whole periodic table and so we go from the UV into the through the visible range and into the a little bit into the IR range as well and that's done or or I should mention some of these elements include uh elements like hydrogen nitrogen carbon and oxygen which are of course all very interesting uh not only

00:05:29 to follow the water on Mars but also to look for uh materials that would be of interest for the exobiology so now I'll turn our attention uh to the Imaging and we do provide context images for the analysis spots these are very small analysis spots and so we want to see what we're shooting at so just to demonstrate that we took a US $1 bill and we uh and we

00:05:52 put it at uh a distance of 10 ft away and and we shot it there um but we'll show you the image and the image in the next slide actually shows uh just the just this part of the dollar bill and from 10t away say those of you in the front row uh you wouldn't be able to see a lot of detail um but this uh image that you can see um up close if it's if it's really uh actually uh expanded you

00:06:17 would be able to see a whole lot of detail on that on that dollar bill and so we provide in the context of these um Libs shots we provide uh an image that has almost the resolution of mics but it's monochromatic we're really doing that just to show us what are what are the uh the samples that we're really shooting at so in summary Kim cam really just provides uh a guide for uh the

00:06:41 other instruments on the Rover to help the help optimize the other instruments and it also provides science in its own right as well Mara Den Associated Press my first question about the Kim cam um you mentioned dusting away the the uh the dust uh do you actually grind or cut into the rock it all with your lasers or is that just you know how deep do you go if you do it all yes so uh it depends on

00:07:08 the uh the hardness of the rock of course and how well the laser couples to it but most rocks were going in say about a micron per laser shot and so we've we've demonstrated uh down to about 600 microns in uh in our testing we actually didn't want to use up we didn't want to use the laser too much before we got to ours and we we we certainly believe we can go down a

00:07:32 millimeter