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OFJ Field Journal from Dave Atkinson - 9/27/95

We are finally getting close. Although I feel like one of the newcomers on Galileo, it has been a very long wait. I joined the Galileo project as an engineer at NASA Ames in 1980, and became involved with the probe Doppler Wind Experiment shortly thereafter. I now have principal responsibility for the experiment, designed to measure the wind profile in the atmosphere of Jupiter by tracking the probe motions via the Doppler shift of the probe to orbiter radio signal. During the last fifteen years I've seen Galileo canceled by Congress and then reinstated, suffered through innumerable delays in the Space Shuttle development, each causing a redesign of the Galileo mission. I watched as the launch date was moved from 1984 (with a 1986 arrival) to 1986 (with a 1989 arrival), to 1989. In 1986 Galileo was at the Cape and preparing for a spring launch when the Challenger accident occurred. And, the day before launch in 1989, the World Series earthquake hit the San Francisco bay area and there were concerns that damage to the facility in Sunnyvale, California responsible for tracking Galileo's upper stage booster might once again delay the launch.

That was six years ago and, following a long, long journey - not only in space but also from the drawing board to the launch pad - we are almost there. Most of my summer was spent at NASA Ames Research Center developing computer code to analyze the probe radio signal frequency data we expect to receive shortly after the probe's December 7 arrival at Jupiter. Summers have always been the hardest time for me, since I must leave my family in Moscow, Idaho (where I teach during the year at the University of Idaho) and come to NASA Ames for six weeks. But, although this summer is no different, it is different. This is the summer of probe release and the countdown to Jupiter. Once again I left for Ames at the end of May, and moved into an apartment in Mountain View, California. Mountain View is located about 15 miles north of San Jose in the San Francisco Bay Area and is home to NASA Ames Research Center. And it was during the first half of July that the excitement really started building. Following a complex series of preparations for probe release that started several days after the 4th of July, it was time to say good-bye to the probe, the orbiter's traveling companion across the solar system, past Venus, Earth (twice), two asteroids (Gaspra and Ida) and one asteroid moon (Dactyl). Several minutes past 11:00 in the evening of July 13 we heard the words over the phone from JPL ``clear indication of probe release'' as the radio signal from the orbiter showed a action/reaction Doppler shift. As the probe went one way, the orbiter recoiled slightly in the opposite direction. After working on the project for fifteen years, it was nice to share this moment with my long time friends and colleagues on the probe - project manager Marcie Smith, probe engineer Charlie Sobeck, probe project scientist Rich Young, and fellow probe experimenters Boris Ragent and Al Seiff. And it was difficult not to think of some of the probe engineers and scientists who contributed so much to the success of the probe and who have passed away in the past few years - Jim Pollack, Carl Privette, Jim Van Ness and Tom Wong.

Following the successful release of the probe I headed to JPL for a probe science meeting, then went home for what was left of my summer. Two weeks after the probe release, the orbiter fired its main engines in a maneuver called the Orbital Deflection Maneuver (ODM). The ODM put the orbiter on the proper trajectory for its encounter with Jupiter. Several weeks later the relay antenna on the orbiter was deployed in preparation to receive the probe signal on December 7.

And now we wait.