APL Colloquium

May 14, 2004

Colloquium Topic: Exploring the Cosmos by “Doing Something Different”

Use of new techniques to exploit dynamical sky phenomena, with spacecraft and small ground-based telescopes, has resulted in solar system and stellar discoveries during a nearly half-century quest. This is adapted from the author's lecture, "Doing Something Different", upon being presented with the 2003 Dirk Brouwer Award of the American Astronautical Society. As founder and president of the International Occultation Timing Association, he has pioneered techniques to measure mountains in the lunar polar regions, the first confirmed meteor impact flashes, asteroid sizes and shapes, and very close double stars, as well as finding evidence for asteroidal satellites a dozen years before Dactyl was imaged by the Galileo spacecraft.

Colloquium Speaker: David Dunham

David W. Dunham has been an astronautical engineer since 1976, first at Computer Sciences Corporation and in APL's Space Department since 1992. His interest in the dynamics of the cosmos began as a teenager when he was active in the Moonwatch program. He began publishing occultation predictions and organizing observations of these events by amateur astronomers in 1962, while at the University of California at Berkeley, from which he graduated in 1964. He received his Ph.D. in celestial mechanics at Yale University in 1971 with his dissertation, "The Motions of the Satellites of Uranus". For a quarter of a century, he has worked with others to design and implement complex spacecraft trajectories that explored the Earth's space weather environment, and resulted in the first flyby of a comet and the first orbiter of, and landing on, an asteroid. He has calculated orbits for numerous space missions, notably for the third International Sun-Earth Explorer/International Cometary Explorer and Clementine while at CSC, then for NEAR-Shoemaker and CONTOUR at APL. Recently, he has worked on orbits for MESSENGER and for possible future missions to land on the far side of the Moon and flyby of comets.