SEEING RED
Interpreting the data and color of Mars

An entire wall of Martha Schaefer's office is covered by a large, panoramic poster of the surface of Mars. Its dusty, cold red surface is illustrated beautifully, but don't let the beauty deceive you. Orbiting the Sun at a speed of 15 million miles per second, Mars is a cold, dry planet with an average temperature of negative 81 degrees Fahrenheit and a thin, mostly carbon dioxide atmosphere.

Using the myriad of data received from satellites orbiting and rovers roaming Mars, scientists are able to generate rich, visual representations of Mars surface such as the poster on Schaefer's office wall. However, art, as beautiful as it may be, is not the main reason why scientists like Schaefer spend so much time analyzing the data beamed to Earth.

Schaefer calls herself a planetary scientist. Her research interest is in the surface and rocks of Mars, so it makes sense that she has joint appointments in LSU's Departments of Geology & Geophysics and Physics & Astronomy. Her work is centered on the cause of Mars’ red surface: oxidized iron.

The soil and rocks of Mars contain high amounts of iron. The condition of the iron in the many minerals of Mars’ surface will give a clue as to how the planet formed, its history, and whether or not life existed or exists on it.

It is impossible to tell what type of iron exists in the rock by simply looking at it. That is where a technique called Mössbauer Spectroscopy can help. In Mössbauer Spectroscopy, rocks are exposed to gamma-rays, which are a form of electromagnetic radiation. By very delicately tuning the energy of these gamma-rays, the iron in these rocks can be made to absorb them. The exact energy of the gamma-rays the iron absorbs indicates what form the iron is in, and also the structure of the minerals in the rock.

With funding from the National Science Foundation, Schaefer uses Mössbauer Spectroscopy to better understand the formation of Mars. When Schaefer can better determine how many types of iron exist, learning the formation processes that Mars has undergone over time will be possible.

"Knowing how the surface evolved will give us a better idea of the possibility for life on Mars and where to look for it," says Schaefer.

Schaefer's work will also help in more uniformly interpreting data between different researchers by making better-tuned software. With the mountains of data being beamed back to Earth every minute from the rovers now on Mars, Schaefer and her fellow planetary scientists have plenty of work ahead of them to determine Mars’ history and its possibilities for life. Thanks to Schaefer's continued work, tackling the data shouldn't be a problem, which will allow scientists to uncover the mysteries of the red planet.

ON THE WEB:
LSU Department of Geology & Geophysics
LSU Department of Physics & Astronomy

from Spring 2005