Mapping Mars!

In the blockbuster film Star Wars, one of the favorite sayings of smuggler/mercenary Han Solo was: "It’s not my fault!" And, despite his role on the National Aeronautics and Space Administration’s (NASA) Mars Site Selection Steering committee, David Crown, assistant professor of geology and planetary science, can say that about the latest mishap with the $165 million Mars Polar Lander.

This mission wasn’t one of the Site Selection Committee’s, and Crown hopes that public opinion over the Polar Lander’s problems doesn’t derail the entire project. The Site Selection Committee was formed to provide advice and assistance on landing site selection for the Mars Surveyor program, primarily for the planned Mars 2001 mission, and those that follow. "Despite several recent setbacks, there is a really exciting program of exploring the surface of Mars, leading up to returning to Earth with samples from its surface in 2008.

"We haven’t yet had the opportunity to study the chemistry of rocks that we know haven’t traveled from Mars through space in the form of meteorites." Crown is referring to the 1996 study of a meteorite, thought to be from Mars, that some scientists believe held fossilized remains of primitive life forms. "Since 1996, NASA has geared its exploration program around finding environments in which life could have existed," said Crown.

"The real thread of that is looking for evidence of water on the surface, or near the surface, and how that may have changed over time. "That’s one of the goals of the program, looking at the data that’s coming back from the Mars Global Surveyor, the spacecraft that’s orbiting right now. We’re trying to get a very detailed view of where water may have been."

The Global Surveyor can spot objects or areas as small as one meter across, which offers a better closeup of the Martian surface than has ever been seen. The surveyor’s newest mission is to photograph the intended landing area of the lander in the hope of spotting a parachute or anything that what happened.

"It’s frustrating, because at this point, we really don’t know what happened. I think some of the changes you’ll see are that they will build in some instrumentation so that, if there’s a mistake, we can learn from it. We don’t expect everything to work perfectly, but we need to know why it didn’t." Crown’s role with the Site Selection Committee relies on his expertise in volcanology and comparative planetology.

"In evaluating landing sites for future missions, we’re trying to explore parts of the planet that may have been affected by water. So, one potential kind of landing site we’re looking for is a hydrothermal spring deposit," he explained. "We know there has been volcanic activity on Mars, and we know that’s an environment where you have heat and water coming together.

"It’s as if you took Yellowstone National Park and turned it off for a billion years—you’d find that kind of environment preserved on Mars. That’s one potential area. Another area is where we see drainage networks on the planet. Those networks may have had water running through them for quite a long period of time."

Crown, who has been creating maps of Mars since 1988, was appointed to the Site Selection Committee in the fall of 1997. Prior to joining Pitt in 1994, he served a two-year post-doctoral research fellowship with NASA’s Jet Propulsion Lab. "I do comparative planetology, and I look at volcanoes on Earth, and volcanoes on other planets. You use your knowledge of Earth and apply it to other planets. You think you know what goes on on Earth, and you can view what goes on on other planets as experiments that are run under different conditions.

Each of the planets has its own unique set of starting points. We can learn a lot about Earth in a comparative mode." This is a real opportunity to increase our understanding of how lavas and magmas work on the Martian surface and to understand the general evolution of the planet, according to Crown.

He says that the Mars program is geared in stages, and the initial stage is to use some of the advanced technology to bring back samples. Eventually, he says, they hope to put human explorers on Mars. "First, we need to build our confidence in getting spacecraft there, getting things into orbit, and learning more about the surface. In the 2001 mission, there is a segment designed by the human exploration component of NASA that’s going to do some soil testing as a precursor for putting people down on the planet."

This story is based on an interview by Sharon Blake and Ken Service that originally aired on Higher Education Review on KQV radio, 1410 AM. H.E.R. is broadcast the first Monday of every month at 7:00 p.m.