Tracking a Comet
People often ask me why the Navy hires astronomers, particularly now that satellite navigation has become the primary means of positioning over the entire planet. The answer is still, “For navigation!”, but the meaning of that term has evolved tremendously since the Naval Observatory was founded. I will briefly describe how the observatory supports the military’s requirements for navigation in the 21st century, and tell the story of how this led to a partnership between USNO and NASA to provide navigational tools for space missions. The biggest challenge to date for space navigation was the Deep Impact mission to achieve an encounter of the explosive kind with Comet Temple 1 in July 2005, and USNO was a key contributor to that effort. I will discuss the intense observing campaign leading up to the dramatic encounter and its surprising results, as well as plans for the follow on mission for the Deep Impact spacecraft.