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Mars Science LaboratorySaturday 4
March 2006
Summary NASA plans to launch their next mission to Mars in
2009, and onboard will be the Mars Science Laboratory, a bigger,
better incarnation of the two Mars Rovers, Spirit and
Opportunity, launched in 2004. On board will be a tiny
laser devise about the size of a cell phone, which will be able to
fingerprint minerals in the Martian soil and rocks. The results will
be put into a data base which reside on Mars.
Program TranscriptRobyn
Williams: Robert Downs, a Canadian at the University of
Arizona, has a gadget meant for Mars that can identify almost any
substance ever.
Robert Downs: I know that
Miami Police Department has about 220,000 spectra of all the illicit
drugs that are out there in the world. You just take these things;
you can shoot them and ten second later you know what they’re
holding: is it baby powder, is it cocaine? Really easy to tell. This
little white powder that came in envelopes that the post office was
getting. Bonner Denton has a demonstration he uses upstairs. He
takes a bottle of Tylenol, a white plastic container and the pills
are inside. You can shoot the Raman and a laser goes through that
white plastic, it identifies the three parts of Tylenol and it tells
you what the plastic is made out of. It works on leaves. I can
identify the species of trees by shooting their leaves. I don’t
think the biologists are aware of this yet.
Robyn
Williams: Can you imagine how useful that could be? Hold
the little gun, shoot the laser and read off what the substance is.
The device is meant to sit on the arm of the Mars rover, and when
you meet Professor Bob Downs to talk about it you’re also meeting a
kind of force of nature.
Robert Downs: Well,
on the 2009 mission nuclear powered machine that they’re going to
put up there, lots of power, and they are going to put this little
device that’s going to be in the order of 200 cubic centimetres in
size and it’s going to sit out as an arm on the rover and it’s going
to come up close to the rocks and it’s going to shoot a laser at the
rocks. And the laser’s going to excite the atoms, make them vibrate
and they’re going to send a signal back - it’s in the order of a
million times weaker than the laser and we’ll see these tiny little
spots of light that the rock emits and we can use them as
fingerprints and we can identify minerals that the rock is made out
of.
Robyn Williams: And you’re making this
device, this little sharp end instrument which is what, the size of
a cornflakes packet?
Robert Downs: A little
smaller than that. I think it’s going to end up being about the size
of a cell phone but we designed it, it was a NASA proposal, started
about three years ago. So you’ve got the big company Hamilton
Sundstrand makes Otis elevators, Sikorsky helicopters, I think they
did some moon landers. So they get these contracts from NASA to
build these sort of devices and Bonner Denton in Chemistry and
myself were the academic side for this project. Bonner designed it;
he knows how to make anything.
Robyn Williams:
Really, what’s he like?
Robert Downs:
Bonner, he’s a Texan, bit of a cowboy, he races cars for a
hobby, he holds the world land speed record 287 miles an
hour.
Robyn Williams: Really – 287 miles an
hour.
Robert Downs: In a sports
car.
Robyn Williams: In a sports car – where
did he do that?
Robert Downs: At the
Bonneville salt flats, and it’s supposed to be street legal but he
tells me the car can’t run on the streets. But an incredible guy,
he’s being doing stuff since he was a kid in the barn, he tells me
he made his first sports car when he was like 13 years
old.
Robyn Williams: Yeah, so he’s handling
which part of the project?
Robert Downs: He
understands the instrumentation, he knows how to make CCD detectors,
how to make the lasers. I understand the material that we want to
investigate, the rocks, the minerals and we make a good team this
way.
Robyn Williams: There you are on Mars
and there’s your instrument looking round at a rock and you shoot
the laser in, how does it tell what it’s got in front of it? It’s
not a chemical sniffer, is it?
Robert Downs:
No, it’s looking at light but when the laser hits the
material, hits the crystal the atoms vibrate, they’re going to
vibrate with different frequencies depending on how strongly they’re
bonded. So silicone oxygen bond for instance is stronger than an
iron oxygen bond so they will show up at different places in the
spectrum. And so you can determine your chemistry and identify the
mineral that you’re looking at – is it a diamond, is it a pyroxene,
is it just clay? You can identify this by the spectrum that’s given
off. The actual spectrographic technique is known as Raman
spectroscopy. It was invented by a man from India in 1928, he won
the Nobel Prize in 1930, a pure quantum mechanical process. We don’t
know how to compute the spectra so the only way we can really
identify things is if we have shot it before, so our idea is that
we’re going to look at everything found naturally on Earth; we’re
going to identify it carefully through X-ray and through electro
microprobes so we know the chemistry and we know the crystal
structure beforehand, then we’re going to shoot it with our
instrument and create a fingerprint pattern that’s going to reside
in the data base that’s going to go up to Mars.
Robyn
Williams: Well if it’s a new mineral unknown to Earth,
what’ll you do?
Robert Downs: In that case,
first of all when you’re sitting on Mars you don’t want to send the
whole spectrum back to Earth, that costs a lot of energy, it’s a lot
of information. So we want to identify things according to what they
match. If we have something new then that’s exciting, we’re willing
to spend the energy and send that whole signal all the way back to
Earth because this is new. We can look at some of the peak positions
and we can say, ah you know, it’s got carbon in it, or it has
phosphorus in it. We may not know what it is right away but once
we’ve got something we can use those clues, its similarity with
things that we already know and we can try to synthesise something
that matches it.
Robyn Williams: And you’ve
got here a prototype pointing at a rock. You’re using that
instrument to test an almost unlimited number of different objects
of different make up around the world. How far have you gone so
far?
Robert Downs: There is about just over
4000 mineral species that are known and we’ve shot about 700 of them
so far; so, one fifth of the way. I think it will be about a
six-year project to complete everything we know found on Earth. And
we’re also looking at the meteorites as well with the NASA
people.
Robyn Williams: And the take-off, as
you say, is 2009?
Robert Downs:
Yes.
Robyn Williams: So you won’t
have completed the number of minerals yet by that
stage?
Robert Downs: By the time the rover
gets there we can also ship data up there, so it’s going to go with
most of the data base. By the time we’ve reached there what will be
missing out of database will be the rarest of
things.
Robyn Williams: The rarest of
things. You can educate your detector when it’s actually on Mars
rolling around?
Robert Downs: Right, it’s
just going to be data stored on a chip so we just send the data
through space and let it record it and put it into its memory
banks.
Robyn Williams: There are rovers
there now and they’ve done remarkably well. Do they have anything
like this instrumentation at the moment?
Robert
Downs: What this last one went up with, the main instrument
was called a Mars bar detector, they inferred lots of things about
the chemistry in the minerals that were found on Mars, but by and
large I think a lot of it was guesswork and they don’t know for
sure. A Raman spectrometer would tell you exactly what you’re
looking at.
Robyn Williams: Yes, indeed.
That’s Mars, how useful could it be for you here on
Earth?
Robert Downs: Yes, that’s a good
question. This project right now, identifying and cataloguing all
the minerals, has been funded by a fellow named Mike Scott, founding
president of Apple Computers. He’s a gem collector and I understand
it’s the second best in the world behind the crown jewels. The crown
jewels were obtained over a long period of time and I think a lot of
people had to die for them to get those jewels; Mike Scott obtained
his the right way – he bought them. Anyways, having this great gem
collection he really wondered how he could ascertain what these
crystals and gemstones that he had, what they really were without
doing damage, because all the tests at the time damaged the crystals
- to do X-ray diffraction you’ve got to bust the stuff up. And so he
got a physics degree at Caltech, a very well-educated man and he
wanted to create such a database for his own interest so that he
could understand his collection, and also I think he understands in
the big realm of things that such a database on Earth would be
useful for everybody. So we can start off with border patrol. I know
that Miami Police Department has about 220,000 spectra of all the
illicit drugs that are out there in the world. You just take these
things, you can shoot them and ten seconds later you know what
they’re holding: is it baby powder, is it cocaine? Real easy to
tell. This little white powder that came in envelopes that the post
office was getting? This stuff you can shoot - Bonner Denton has a
demonstration he uses upstairs. He takes a bottle of
Tylenol.
Robyn Williams: That’s headache
powder.
Robert Downs: Yep, white plastic
container and the pills are inside. You can shoot the Raman and the
laser goes through that white plastic, it identifies the three parts
of Tylenol the aspirin and it tells you what the plastic is made out
of. It works on leaves – I can identify the species of trees by
shooting their leaves. I don’t think the biologists are aware of
this yet. I have a friend who collects snakeskins, I shot the
snakeskins and I can identify the species of snake. Last month
researchers in Switzerland showed that with the Raman instrument
they could detect breast cancer. So we don’t know where this is
going, it’s a brand new technology basically made because NASA
funded it to make it cheaper, created the new optics and so on. And
then we have people like Mike Scott, who’s willing to put their own
pocket money out to actually create the databases required to
identify things.
Robyn Williams: That’s
fantastic. I’ve just seen the quarter of a million dollar instrument
and the slightly cheaper but bigger one you’ve got to pioneer this,
and now you hope to get the one in front of me down to about $5000 –
that’s very cheap.
Robert Downs: I think
$2000 to $5000. The reason it’s happening is that the
telecommunications industry, with all these fibre optics, have
designed all these miniaturised circuitry and so on that works
beautifully for this and nobody knew about this, including NASA,
until this research project to create the instrument came along and
Bonner Denton, who just has his hands in everything, put the two
parts together and we have this industry Axon Technologies, they’re
in Cambridge, Massachusetts, they’re sitting there with warehouses
that just weren’t being used because there’s been a downturn in the
telecommunications industry. Bonner comes along, he sees the
relationship between our instruments and what they have built and
he’s putting the two parts together. And we figure by June, they’re
telling us, the first prototype will be on the
market.
Robyn Williams: Anyone tells you
that space exploration is a waste of money, what do you
say?
Robert Downs: Microwave ovens: invented
by NASA.
Guests on this program:
Dr Robert Downs Mineralogy and
Crystallography Department of Geosciences University of
Arizona http://www.geo.arizona.edu/xtal/group/index.php3?page=home
Further information:
NASA - future Mars missions http://mars.jpl.nasa.gov/missions/future/msl.html
Presenter: Robyn Williams
Producer: Polly Rickard and David Fisher |
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