Sky & Telescope remembers Steven J. Ostro, 62, JPL PI, pioneer in radar investigation of NEOs and asteroids
Kelly Beatty - The worldwide community of planetary scientists has grown tremendously since I started covering the solar-system beat in the mid-1970s, and a great many of them are friends. So too was Steve.He and I crossed paths in the mid-1980s, not long after he joined JPL's planetary-radar group. Steve basically invented the technique of using powerful radar antennas to probe asteroids, beginning with a successful "ping" of the main-belt heavyweight 1 Ceres while a graduate student at MIT.Steve realized radar's potential not only for determining the surface characteristics of small rocky bodies but also for pinpointing their line-of-sight distance and velocity with incredible accuracy. Guided by his skill at wringing absolutely every bit of information from a radar echo, both of these capabilities became powerful analytical tools in the effort to understand near-Earth asteroids and the threat they pose to Earth.