While most of the 2003-2004 MER (Mars Exploration Rover) team is focused
on studying the surface of Mars, Dr. Mark Lemmon, along with a small
group of fellow scientists, will study the planet's atmosphere. Many
people fail to realize that Mars has an atmosphere. It's very thin and
mostly made of up of carbon dioxide. The Martian soil contains iron
oxide or 'ordinary rust', and when it gets blown around by the wind, it
often hides the surface. This 'rusty dust' gives Mars its reddish skies.
Lemmon is an Associate Research Scientist in the Atmospheric Sciences
Department at Texas A&M University in College Station. He usually works
in his Texas office, but frequently travels to Los Angeles to work
closely with the other rover scientists. These days, Lemmon and his
colleagues are practicing surface operations at JPL (the Jet Propulsion
Lab). This way, when the time comes to perform the operations on Mars,
the team will be ready. "When we talk about 'testing' and 'training,'"
Lemmon says, "we often mean that we are pretending to explore Mars by
driving a rover around in either a giant sandbox or in the desert." This
kind of "training" is hard work, but it's also very exciting.
Mark (front right) with the surface stereo imager team from Mars Polar Lander
When Lemmon is in Texas, he works with his computer much of the time. He
uses telescopes on Earth to take pictures of Mars or Titan. Sometimes,
the telescopes are in Texas, and sometimes they are in Hawaii--and
sometimes he controls the cameras on a telescope in Hawaii while working
at his desk in Texas. "It is pretty strange to be using a big telescope
over the Internet when there is a thunderstorm going on just outside
your window," remarks Lemmon. These specialized scientific tools help
him to analyze images in order to make sense of what he observes in the
atmospheres of other planets.
Lemmon is currently working with the other scientists to learn how to
best use the rovers. Every day that the rovers are on Mars, the clock
will shift slightly. A Martian sol (day) is almost 40 minutes longer
than an Earth day. "We'll all have 'Mars lag',' explains Lemmon, "so we
need to have a nice easy way to make the commands for the rovers."
Once the rovers land, Lemmon's role will shift from preparing for the
mission to analyzing the data and planning the next sol's activities.
He'll pay close attention to the images of the sky and sun to study and
measure the Martian dust. The engineering team is extremely interested
in these measurements: the more dust there is in the sky or on our solar
panels, the less solar power the rovers will receive. If the rovers do
not have enough power, they will not be able to move around.
The MER mission should produce images that no one has ever seen before.
Lemmon is excited about the 'stories' that these images could reveal
about the planet. There is ice buried underneath the surface, and this
is interesting because it seems that anywhere there is water on Earth,
there is life. Since Mars' climate changes over time, "nobody knows just
what Mars may have been like when the ice was in liquid form," explains
Lemmon, "but it would be cool to find out if life could have existed in
this type of environment."
Sunset from Mars Pathfinder, night of Sol 24
Lemmon has been drawn to science since he was a kid. He enjoys seeing
new sights, and figuring out how things work. "I've always liked going
up into the mountains," he says. "It's exciting to take on a challenge
and be rewarded with a view that would have been unattainable at the
trailhead. Science is just another way of seeing over the next hill."
Mark with the Lego MER at Kennedy Space Center