Online From Jupiter 97

Dennis Byrnes

Lead Trajectory Optimization Engineer

My name is Dennis Byrnes. I am the lead trajectory optimization engineer for the Galileo Navigation Team. The Galileo spacecraft (the atmospheric Probe and the Orbiter) will arrive at Jupiter on December 7, 1995. As part of my trajectory design job, I was one of the people involved in deciding back in 1988 that this would be the best day to arrive at Jupiter. My involvement with the Galileo Mission goes back even before it had that name. I began work on what was then known as the "Jupiter Orbiter Probe" or JOP for short, in the Fall of 1977. To put this into perspective, my son had just started the first grade when I started work on JOP. He is now in his fourth year of medical school and will be a practicing medical doctor when the mission is over in 1997! My work in the early years of the mission was to help design the complicated orbit around Jupiter that goes by Jupiter's satellites as many times as possible. Now as part of the Navigation Team, I help keep the spacecraft as near to the designed orbit as possible.

I became interested in science at a very early age. By Junior High School I had decided that astronomy and space science were what I wanted to do. Even though Sputnik had not yet been launched, landing on the Moon was my goal. I have been an avid reader of science fiction since I was in the third grade and this has surely influenced my decisions about my career. After high school, where I took as much math and science as I possibly could, I went to the University of California at Berkeley and majored in physics. I also received a Master's Degree in astronomy and completed all of the course work for a Ph.D. I left school in 1968 before finishing my Ph.D. and went to Houston to work on the Apollo Program because I couldn't stand not being involved in the first manned landing on the moon.

Designing and using the computer programs to find trajectories that go by planets and satellites is for me a lot like playing a video game. Many very complicated things are happening all at once and it is my task to thread my way through it. It is great fun meeting this challenge and they are paying my salary to do it! On the other hand there are always reports to write and meetings to go to. This can sometimes be the boring aspect of the job, although it is nevertheless a very important part of it.

As I mentioned, I read a lot of science fiction when I was young and I still do ("hard" sci-fi, not fantasy). When I was in Junior High I had an area of the garage that a friend and I were allowed to use. We built model rockets from scratch (this was long before the commercial ones were available) and we learned a great deal even though they didn't work very well. I was very lucky to have Junior High and High School math and science teachers who encouraged me and stretched my imagination. My parents were always tolerant of my "weird" experiments and interests and encouraged me to do things that interested me. My wife and I have tried to do the same with our children. My daughter majored in history and psychology in college and now is the operations manager for a convalescent hospital. My son, like myself, is an avid sports fan and since he is 6'5" has played basketball through high school and college. He is in his fourth year of medical school and plans to specialize in sports medicine. I like to watch most sports and am an avid racquetball player. That and regular jogging are how I stay in good physical shape,