Completing the Inventory of the Solar System

点击翻译按钮获取中文摘要

Dr. Scott Sheppard is awarded an NSF Astronomy and Astrophysics Postdoctoral Fellowship to carry out a program of research and education at the Harvard-Smithsonian Center for Astrophysics. To help complete the inventory of small bodies in our solar system in order to understand planet formation and evolution, Dr. Sheppard will perform dedicated surveys unobtainable by and thus complimentary to future planned large surveys such as Pan-STARRS. The surveys will search for distant Sedna-type objects beyond the Kuiper-Belt edge, very large dwarf planets in the Southern Hemisphere, extremely faint Kuiper Belt objects, and objects interior of Earth's orbit. These selected observations are intellectually important because: 1) Like Pluto before, Sedna may just be the tip of the iceberg of a population in the distant Solar System. Sedna's distant perihelion does not currently fit into our ideas about solar system formation. Discovering more Sedna type objects may constrain our Sun's star cluster formation environment as well as the extent of the original solar nebula. 2) The largest Kuiper Belt objects are very rare but extremely important since their brightness allows modern spectroscopy to reveal their surface compositions. 3) The extremely faint and thus smallest Kuiper Belt objects are expected to be the progenitors of the short period comets. The small end of the Kuiper Belt population may be severely under abundant calling into question the source region of the comets. 4) Finally, the near Earth objects interior to Earth's orbit are a severe Earth impact hazard which has not yet been fully explored.Dr. Sheppard will also work with the Center's Science Education Department (SED) to develop and update interactive astronomy displays to be exhibited in museums and institutes. He will also lead a web blog run by the Smithsonian discussing recent astronomy events.