So maybe we haven't found little green men yet, but the news that scientists have discovered what they call "compelling" evidence of possible microscopic life forms on Mars has prompted much end-of-the-world-as-we-know-it rhetoric. The findings, if they are as dramatic as suggested, were put through their initial paces at Stanford University, where a highly sophisticated laser mass spectrometer analyzed the meteorite samples for a common family of organic molecules called PAHs. The spectrometer also found other compounds -- iron sulfides and magnetite -- that are produced by bacteria and other microrganisms on Earth.
We talked with Seb Gillette, 28, a graduate student in chemistry at Stanford University who worked with Professor Richard Zare and the Mars team for the past six months, analyzing data from the spectrometer.
Some people think the moon landings and other space shots are frauds staged on some Hollywood sound stage. This couldn't be some kind of hoax could it?
Uh... no. No possibility.
Somebody couldn't have taken a piece of ordinary rock and done some things to it and sort of plopped it in Antarctica, where probers found it?
Well, the molecules we discovered were deep inside the meteorite found in Antarctica. Also most of the work that we did was to run "blanks" (material other than the actual rock sample) to check for possible contamination. Running the actual sample was a small part of what we did.
Still, it's probably the most significant thing you've ever done.
Louis Freedman of the Planetary Society said, "This changes our view of ourselves. It changes our view of the universe." Is that true?
I don't know if it changes the view of ourselves. You know, these are very small bacteria. But it does maybe change the view of our universe.
In what way?
Well, just that if there's precursors of life on a planet right next to ours, then there may be other planets in the solar system that have the same thing -- and maybe more advanced life forms.
But it's a long stretch from "precursors" of life to life forms. Is the finding of possible precursors elsewhere in the universe such a big deal?
Um... I guess it's a question that a lot of people ask themselves. Are we alone? It's just interesting.
Here's a quote from President Clinton: "If this discovery is confirmed, it will surely be one of the most stunning insights into our universe that science has ever uncovered. Its implications are as far-reaching and awe-inspiring as can be imagined." Does that sum up the way that you feel about it?
I think it does, in a way. But in another way, because we spent so much time on it, and things developed really slowly, I've maybe become callous. I wouldn't say callous, just used to the fact. So it's not that stunning.
The actual process of discovery of possible alien life forms is not like what we see in the movies?
Well, you have to tune the spectrometer -- setting the power on the lasers, and the electronics to trace the samples' "time of flight." That takes maybe two hours, depending on how it goes. The samples are sliced or ground and could weigh less than a milligram; meteorites are, like, sedimentary so they crumble pretty easily. Then you run a sample through the spectrum, which is shot through two different lasers. That takes a couple of microseconds. The broken-down molecules create a signal which is stored on an oscilloscope. Then you wait for the computers to spit out the data on the weight of the molecules, and so forth. And like I said, a lot of it is to check for contaminants.
How do you do that?
We had some meteorite samples also from Antarctica that weren't from Mars, that were subject to the same kind of weathering. So you analyze them to see if they have the same kind of chemical properties as the Mars sample.
After a while it must feel like a pretty boring process.
Yeah, in a way. But in another way you're surrounded by flashing lasers and racks of electronics.
And the computers -- they're probably giant number-crunching Cray supercomputers.
Oh, no. They're just IBM PCs. We used a 166 Mhz Pentium.
So you could almost do this at home -- except for the lasers.
(Laughs) Yeah, sometimes I'd take the data home with me. But it's an experience. The technology that went into the spectrometer is just overwhelming. They've been building and modifying it for eight years.
Members of the team say they expect their findings to be challenged -- and that has already begun. And they acknowledge that a lot more testing needs to be done.
Definitely. Any of our findings alone could be explained; even together some of them could be explained. But the presence of what looks like bacteria, and the presence of organic molecules -- it's that combination that would lead one to believe that maybe it was life. But they're definitely not conclusive results.
What are you going to be doing next?
The spectrometer has many different applications. We're also looking at soil samples from Earth that could be used to identify new antibiotics. I'll be staying in school for the next three to four years. Try to get my doctorate degree.
Keeping them down on the farm
"Am I supposed to stand around while my daughter chases men? So what if some infidel doctor says it is unhealthy? Does that make it true? I would have circumcised my daughter even if they passed
a death sentence against it."
-- Said Ibrahim, 53, an Egyptian farmer who opposes the Egyptian government's government ban on female clitoridectomy, because he believes it would encourage sexual aggression among women. (From "Mutilation of Egyptian Girls: Despite Ban, It Goes on," in Thursday's
New York Times