       |
|
Earthbeat All in the Mind Health Report Ockhams Razor In Conversation The Buzz Science Show The Lab Catalyst Quantum Science News |
 |
Saturdays at 12.10pm, repeated Mondays at
7.10pm with Robyn Williams Mars Science LaboratorySaturday 4 March 2006SummaryNASA 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 Further information:NASA - future Mars missions Presenter: Robyn Williams Producer: Polly Rickard and David Fisher |
|
|
| |||||||||||||
.gif){kind=spacer}
