Mars Surveyor 2001
Missions Take Shape

The biggest surprise for the Arizona State University (ASU) TES group, headed by Dr. Phil Christensen-- the 2001 missions will include new instruments based on the Mars Global Suveyor TES project! Mars Surveyor 2001 has three components-- an orbiter, a lander, and a rover. Christensen's ASU team was selected to participate in the rover and orbiter projects.

Figure: Athena Rover diagram.

Athena!

The rover is named Athena. The rover and lander are planned to launch together in April 2001. The landing is slated for January 2002. Athena has a lot in common with the 6-wheeled Sojourner that operated on Mars this past year, but she is bigger and carries more science instruments. In fact, Athena has a small drill to collect cores from rocks. These rock samples might eventually be returned to Earth via a Sample Return spacecraft that could reach Mars as early as 2006.

The leader of the Athena science team is Dr. Steve Squyres of Cornell University (Ithaca, NY). Several years ago, Squyres assembled a team to propose a rover for Mars. After several proposals and much, much work, the rover was finally selected in November 1997. It is planned to drive around for up to 365 days, collecting and examining rocks at a site that has yet to be selected (the hope is to pick a site of potential biological significance).

Mini-TES

The TES on Mars Global Surveyor (MGS) now has a child of its own! Athena will carry a miniature version of TES, smaller than a soda-pop can. The Mini-TES will be built by the same people at Hughes Santa Barbara Remote Sensing (in Goleta, CA) that built the MGS TES. Mini-TES will help the Athena team select rocks to study and sample. Mini-TES is a project from ASU and Dr. Christensen.

Figure: 2001 Orbiter diagram.

2001 Orbiter and THEMIS

The Mars Surveyor '01 Orbiter is expected to launch in March 2001 and reach the Red Planet in December 2001. It carries two instruments linked to Arizona-- The Gamma Ray Spectrometer (GRS) is from a University of Arizona team headed by Dr. William Boynton. The GRS is a replacement of the similar instrument that was lost on Mars Observer in 1993.

The other Arizona instrument is called THEMIS (Thermal Emission Imaging System). THEMIS is headed by ASU's Christensen, and will also be built by Hughes Santa Barbara Remote Sensing. THEMIS can make thermal infrared images of Mars at resolutions of about 100 meters per pixel (whereas TES has a resolution, at best, of 3,000 meters per pixel). Like the MGS TES, THEMIS will map the mineral composition of the martian surface-- only this time it will do so with more detail than the TES currently in orbit.

THEMIS also includes a visible-light camera system that can provide pictures of Mars at about 20 meters per pixel. This additional camera is being provided by Malin Space Science Systems (San Diego, CA). Like TES, THEMIS will be controlled at ASU in Tempe, Arizona.

Beyond 2001

After the 2001 missions, another orbiter, lander, and rover are being planned for launch in 2003. These are expected to be followed by a mission in 2005 that will retrieve rocks collected on Mars by Athena or the 2003 rover, and bring the samples back to Earth by 2008. Depending on funds, another Sample Return mission could follow.