2005 Isaac Asimov Memorial Debate: Enigma of Alien Solar Systems

Wednesday, March 30, 2005

When the first planets were discovered around other stars nearly a decade ago, everyone expected these alien solar systems to resemble our own, with small, rocky planets close to their host star and larger, gaseous planets farther away. However, not one of these planetary systems holds these properties. Currently, these systems contain one or more Jupiter-sized planets orbiting as close to their host stars as Mercury orbits our Sun. These systems stump observers and theorists alike forcing us to look anew at our own Solar System and ask the question, Are we the enigma?


  • Fritz Benedict—University of Texas. Long-time observer and weigher of extrasolar planets using the Hubble Space Telescope.
  • Paul Butler—Carnegie Institution of Washington. Co-discoverer of more than two-thirds of all known extrasolar planets.
  • Peter Goldreich—California Institute of Technology. Theorist with expertise on the formation of planets, asteroids, and comets.
  • Scott Tremaine—Princeton University. Expert on the gravitational interactions, orbital dynamics, and long-term stability of planetary systems.
  • Margaret Turnbull—Carnegie Institution of Washington. Next-generation planet-hunter and world-expert on habitable zones around stars in which we hope to find planets capable of sustaining life.

Host & Moderator

  • Neil deGrasse Tyson—Astrophysicist and The Frederick P. Rose Director of the Hayden Planetarium.