Online From Jupiter 97

Byron G. Yetter

Deep Space Tracking Network Operations Project Engineer (NOPE)

During my Grade school days the Apollo Missions were on the television and in everyone's imagination. Radio controlled airplanes and "Estes" model rockets occupied a lot of my free time. Space exploration and Flight in general have always been two of my foremost passions. After 4 years in the United States Air Force where my duties involved Air to Air and Air to Ground Aircraft launch Missile systems, (The "Estes" rockets just got a little bigger), I began to look to the stars. I was lucky enough to land a job which allows me to continue my passion for space exploration. My passion for flight continues as I work on the multi engine and instrument ratings of my current pilot's license.

The Deep Space Network (DSN) is a world wide space tracking system that consists of three multiple antenna complexes. These three complexes are located equal distances apart from each other. The even spacing around the Earth of these complexes allows for continuous tracking of deep space and near earth satellites. The US (DSN) complex is located 150 miles north of Barstow, California. Another complex is in Madrid, Spain, and the third located in Canberra, Australia.

Each complex contains 6 to 8 Radio Frequency tracking antennas. These antennas are of different sizes and configuration used to support specific space communications applications. The Galileo Spacecraft is tracked with the largest antennas at each complex. The 70 meter (310 foot) diameter antennas receive and amplify the very weak radio frequency signals being transmitted to Earth from the Galileo transmitter. The 70 meter antennas also provide a high power (100 Kilo Watt) transmitter to send commands to Galileo. These commands may be a simple "turn on a heater in the radio bay of the Galileo Spacecraft," or they may be a series of commands which allow the Spacecraft to function and perform using an operational sequence. The Deep Space antennas are shaped much like the new home entertainment satellite antennas (a bowl shape), but are *much* larger. From one edge of a 70 meter antenna to the other is roughly the length of a football field, end zone to end zone.

During my exciting Deep Space Tracking career Galileo and I have crossed paths three distinct times. The first time was in 1986 when I began working in the Compatibility Test Area (CTA-21) at JPL. This facility supports testing of all spacecraft which will be "supported" by the DSN. During 1986, Galileo was being assembled, and was having all of its on board systems tested to make sure that they were space worthy. Once this testing was completed Galileo and I parted. My second encounter with Galileo came in 1989 when I was promoted and sent to the Kennedy Space Center in Florida to supervise the DSN launch support facility known as MIL-71. This facility provides all the equipment required to emulate a DSN station. During pre-launch support final Spacecraft compatibility testing is completed, and the MIL-71 equipment provides a vital communications link between the spacecraft and its JPL Mission controllers. Once Galileo was launched on October 18th 1989, again Galileo and I parted.

In 1992 I was again promoted to my present position of the Galileo DSN Network Operations Engineer. My duties include a wide range of activities using my extensive DSN experience. Currently I meet with the Galileo Project and provide the plans and testing needed for successful DSN Mission support. So, over the past 9 years, I have been lucky enough to see the Galileo spacecraft being assembled and launched--and now I will watch her complete her most important tasks.