The discovery of Sedna suggests a population of icy bodies residing far outside the Kuiper belt. With a perihelion of 76 AU, Sedna is well beyond the reach of the gas-giants, and unlike typical Kuiper belt objects, could not be scattered into its highly eccentric orbit from interactions with Neptune alone. Its aphelion of 1000 AU is too far from the edge of the solar system to feel the perturbing effects of passing stars or galactic tides. Each of the proposed scenarios offered to explain Sedna's formation leaves a distinctive imprint on the members of this distant population. The orbits of these distant planetoids are likely dynamically frozen in place providing a fossilized record of their formation. Sedna is the only body known to reside in this region. Finding just a handful of these bodies, we can begin to read this dynamical record. In order to find the largest and brightest members of this population, we have been engaged in a two-year observational campaign to survey the northern sky using the 1.2-m Samuel Oschin Telescope located at Palomar Observatory. We have surveyed 11,000 square degrees within +/- 30 degrees of the ecliptic to a depth of R magnitude 21.5; making our survey the largest search for inner Oort cloud objects to date. We present the results of our survey, and we place new constraints on the size and distribution of a Sedna-like population.
AAS/Division for Planetary Sciences Meeting Abstracts #40
- Pub Date:
- September 2008