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PSI MGS Web Site:
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 Mars Global Surveyor Launch: Eye witness painting done on site at Kennedy Space Center. Copyright William K. Hartmann. |
Dr. William K. Hartmann, a senior scientist at PSI, is a Participating Scientist on the Imaging Team of NASA's Mars Global Surveyor Mission. (25 years ago, he also served on the Mariner 9 mission, which was the first to map mars in detail, and produce discoveries of the river channels and other features).
This project has also involved a number of NASA Space Grant students. Gregg Herres was the lead Space Grant student during the first year of the mission, and much of this MGS page design was completed by him. The project has also been assisted by studen t staff members Gil Esquerdo and Alejandro Diaz. In Madrid, Spain, student Jorge Anguita and Miguel de la Casa are collaborating with the crater counting on new MGS images.
What will Mars Global Surveyor (MGS) tell us?
The spacecraft entered orbit around Mars in September 1997. The wide angle and telephoto cameras worked beautifully from the first orbits, and returned images of many regions of Mars. Under the best conditions, the telephoto camera images objects as sma ll as a few meters across -- the size of a car. We are using these images primarily to study populations of impact craters on Mars. These can give us clues to the erosion rates of Martian surfaces, as explained in Cratering Stud ies.
Among photos from the first days of the mission were this striking oblique view across the ancient dry river channel, Nirgal Vallis. Nirgal Vallis was studied by Viking Orbiter photos in the 1970's, but the much higher resolution views from MGS reveal fo r the first time a beautiful row of dust dunes deposited on the channel floor. As Martian winds move across the surface, they apparently drop their load of dust as they enter a channel depression or a crater, leaving a dune deposit.
 Viking photo of Nirgil Vallis river channel. (142 KB) |
 Closeup oblique view of part of the channel, showing dunes. (639 KB) |
We can expect many more detailed photos of various features on Mars, as the orbit continues to be adjusted. Many exciting features on Mars have already been targeted by the camera system. The pictures will be matched up with spectral data from the "TES" (Thermal Emission Spectrometer, built at Arizona State University), to interpret geological history and composition of various geologic units on Mars. For example, we can search for deposits of evaporite minerals that might have been left my ancient lak es or seas as they evaporated.
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