Associated Press

This handout image shows an artist's rendering of the 2001 Mars Odyssey spacecraft, which was expected to arrived at Mars yesterday at 7:30 p.m., according to NASA. The Odyssey was scheduled to execute a braking maneuver yesterday and ease into orbit around Mars for a 2 and 1/2-year, $297 million mission to study the makeup of the planet and look for frozen reservoirs of water.

Wednesday October 24, 2001

UA faculty, guests watch 2001 Mars Odyssey arrive at Mars last night

An anxious group of scientists watched from Kuiper Space Science's Lunar and Planetary Laboratory yesterday evening as a spacecraft carrying a system designed by UA scientists entered Mars' orbit.

The University of Arizona-designed Gamma Ray Spectrometer - which analyzes the distribution of chemical elements on Mars in order to determine whether water ever existed there - arrived at the red planet on the Mars Odyssey, a spacecraft launched in April.

"This is a big key to understanding if life could have gotten started on Mars," said William Boynton, a UA planetary scientist who led the team that designed and built the GRS.

As the spacecraft neared Mars, it began the complex and risky procedure of entering the planet's orbit.

Precisely on schedule, the Odyssey sent a signal indicating that it had reached orbit and was online. Then it disappeared behind Mars, beginning its orbit, and was unable to communicate with Earth for 20 minutes.

As it emerged at 8 p.m., the Odyssey sent another signal indicating that it was back online and had begun its orbit of Mars.

As NASA received the signals, scientists from around the city watched a real time update of the satellite's progress.

JON HELGASON

Gamma Ray Spectrometer Principal Investigator William V. Boynton celebrates the successful burn of rockets on the Mars Odyssey Probe that obtained its orbit around Mars. The GRS project was originally proposed in 1984, failed once aboard NASA's Mars Observer in 1993 and finally appears to have succeeded with the entry of Odyssey into Martian orbit.

When the initial signal was received, observers at NASA and LPL broke into applause. Then they waited for the Odyssey to re-emerge from its 20-minute blackout period.

When the second signal was received, the scientists burst into celebration. One shouted, "We're here!" as the crowd applauded and popped champagne corks.

This "burn" of the engines is a complex process that has failed in the past, as it did in 1993 when NASA's Mars Observer entered the Martian atmosphere and was lost. That spacecraft was carrying the original GRS.

Dave Hamara of the GRS team, worked on the Mars Observer and the 1998 Mars Lander, both of which failed during the critical stage of orbit entry. Hamara said he was relieved that the Odyssey made it.

"I'm one for three," he said.

The GRS is a combination of instruments, including a gamma sensor head and two neutron spectrometers. Combined, these devices will help to confirm the presence of water on Mars by analyzing the Martian soil's chemical composition and mapping the exterior of Mars for surface waters.

Bill Feldman, a Los Alamos National Laboratory scientist who developed the neutron spectrometers, co-wrote the initial GRS proposal 17 years ago, and witnessed the 1993 failure.

"I've got my whole soul into this," he said.