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December 13, 2002
An
Out-of-this-World Interview with Darby Dyar
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Photo: Paul Schnaittacher
Associate
Professor of Astronomy and Geology Darby Dyar has received
a $150,000 grant from NASA to conduct research for the space
agency's Mars Exploration Rover Mission.
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So
much like Earth in so many ways, Mars holds intriguing secrets:
Did it ever have the kind of oxygen-rich atmosphere needed to
support life? Did oceans and rivers once flow on its now-dry surface?
And, if so, what happened to the water? Darby Dyar, MHC associate
professor of astronomy and geology, has received a three-year,
$150,000 grant from NASA to help seek answers to these questions
by conducting research for the space agency's Mars Exploration
Rover Mission, set to land a pair of rovers on the red planet
in January 2004.
Among the six instruments
in each rover's tool kit will be a Mossbauer spectrometer,
a device designed to study iron-bearing minerals on the planet's
surface. The Mossbauer spectrometer data will be of little use,
though, without the key that Dyar will provide. Scientists know
how to read spectrometer results taken at normal Earth temperatures,
but not at the –208¾ F. temperatures found on Mars. Using
the College's Mossbauer laboratory in Clapp Laboratory, Dyar
and her student assistants will gather data on about sixty minerals
they might expect to find on Mars, chilling the samples during
data acquisition with a liquid helium refrigerator.
David LaChance, CSJ
writer and College media relations associate, sat down with Dyar
one morning to learn more about her research.
If the mission
is a success, what are we going to learn about Mars?
What we're going
to learn is which minerals exist on the surface of Mars. How does
that relate to the question about water? Some minerals have hydrogen
in their structures when they are found on Earth, and so if we
find those minerals, that tells us that there was water around
at the time the minerals were crystallized. Even minerals that
normally don't have water in them, like olivine, occasionally
have minute quantities of hydrogen in them, which, if added up,
again could tell us that there was water at the time those minerals
crystallized.
We
have been to Mars a couple of times. Don't we have some idea
of what's there?
We have, except that
chemical analyses that we got from Mars, both on the Viking mission
and on Mars Pathfinder, were very much biased by the dust. Mars
has global dust storms, and also dust devils. So the problem is
that everything on Mars is coated with a thick layer of dust.
The rovers will carry something called a RAT, which is a NASA
acronym for "Rock Abrasion Tool," that will grind the
dust off and give us a direct look at the rocks.
Why go to Mars
in the first place?
My father always gives
me grief about this one—and then I remind him that Mars Pathfinder
cost less than production of the movie Waterworld! The stated
NASA reason for going to Mars is the search for water and, related
to that, the search for life. Finding or not finding life, DNA-based
or some other form, would be a profoundly important discovery,
not just for science but for theology and a whole range of other
aspects of the human condition. That's huge reason number
one. And huge reason number two has to do with biological imperative.
Sooner or later I think it's going to become important for
human beings to look at Mars as a possible place to live, or to
get resources that will enable us to continue to live on Earth.
How did you
get into doing this work for NASA?
I ran out of money
my senior year at Wellesley, and I got a job working for Roger
Burns at MIT, doing computer programming. He talked me into going
to graduate school to work with him at MIT, and changed my career
path from being either an art historian or a field geologist to
being a lab scientist. The next thing I knew, NASA was paying
me to go to graduate school and study lunar rocks. Before I got
my first teaching job, at the University of Oregon, Roger sat
me down and said, "Darby, the world of Mossbauer is not big
enough for the both of us. We're going to have to divvy up
the turf. I will do extraterrestrial stuff, and you will do terrestrial
rock." Which is how the arrangement worked for several years.
Then, in 1993, he died of stomach cancer, very suddenly. And the
community was sort of shocked for a while, and then six months
later people started calling me and saying, there's a huge
vacuum in this field, because Mossbauer is really important, but
there aren't very many people who do it. So I came back.
There's
been a lot said and written about getting more women into science.
How are we doing, and how in particular is NASA doing?
NASA is not doing
a very good job. The most recent manifestation of this was that
the Mars Exploration Rover science team had eighty people apply
to be participating scientists on the mission, and of those eighty
people, thirty were chosen, and of the thirty only two were female.
And that was despite the fact that sixteen out of the original
eighty were female. So, basically, one-fifth of the original applicants
were female, and one-fifteenth of those chosen were female.
Coincidence?
No, it's not
coincidence. NASA has always chosen to make its awards strictly
on the basis of scientific merit. One of the frustrating things
about that philosophy is that it does not recognize that even
in the new millennium, judgments of scientific merit are not made
without bias. The other funding organizations, like the National
Science Foundation, have made a special effort to develop programs
for women and minorities. NASA has not done any of that. So NASA
has been very unforgiving when it comes to the needs of underrepresented
groups. I refuse to believe that twenty-eight out of sixty-four
men wrote proposals with scientific merit, but only two out of
eighteen women wrote meritorious proposals.
How are women
doing in the sciences in general?
Mount Holyoke has
started cohosting a reception at the Lunar and Planetary Science
Conference for women, and it's very sad how few women of
age thirty or older are in attendance. There are biological factors
that affect women and their progress through the scientific careers.
The way academic life is structured—Ph.D., and then assistant
professor, and then tenure, and then the rest of it—is in
direct competition with a woman's most productive time biologically.
And the reason that timetable exists is that it was set up at
a time when only men were faculty. It's historical precedent—you
can't knock the men for that—but what we can knock is
the fact that we have not in the modern era reconsidered that
timetable and its conflict with a woman's biological clock.
Does it matter whether it's a man or a woman doing
this work?
Yes. I think I am
a better scientist for this project because I'm female, and
I am used to taking strands of many different fields and bringing
them together into one coherent whole. But the most important
answer is that it makes a huge difference for the students. I
got into geology because I had to take a science course at Wellesley,
and Introduction to Geology, which was supposed to be the easiest
science course, was taught by a woman. I just had never been around
a woman scientist, so it never occurred to me that I could be
one. Although we're in the new millennium now, my students
who have taken earth science in junior high or high school tell
me that their teachers were almost always male. So that stereotype
still hasn't gone away. I think it's also really important
for my students to see me juggling my professional and family
responsibilities. I have on more than one unavoidable occasion
brought my children to class with me, and I don't know if
I would be bold enough to do that at a non-women's college.
Will people
ever set foot on Mars?
We'll get there
in my students' lifetimes. I don't know if we'll
get there in my lifetime. I hope we do. If we find evidence for
water in the missions over the next decade, the next step is going
to have to be sample returns from Mars, or people going. Miraculously,
we have the technology to transport hydrogen to the Martian surface,
and extract oxygen and carbon from the atmosphere to make rocket
fuel for the trip back. If we have that technology, we also have
the technology to actually live on the Martian surface for extended
periods of time, and I think it's going to happen.
The
counter is
2,175
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