Font Size: a A A

Small bodies in the outer solar system: From Kuiper Belt objects to Centaurs to satellites

Posted on:2005-06-28Degree:Ph.DType:Thesis
University:University of Hawai'i at ManoaCandidate:Sheppard, Scott SFull Text:PDF
GTID:2452390008996429Subject:Physics
Abstract/Summary:
This thesis is split into two parts. Part one describes Kuiper Belt and Centaur work and part two describes outer satellite surveys of the planets.;A wide-field survey was conducted near the ecliptic in search of bright Kuiper Belt objects and Centaurs. It was determined that the Centaur population is of order 1 × 107 (radius ≥1 km) assuming a geometric albedo of 0.04. The Centaur population taken along with their average dynamical lifetime is consistent with the Kuiper Belt as the source of the Centaurs. The current total mass of the Centaurs is 10−4 M⊕.;In the Hawaii Kuiper Belt Variability Project nearly 40 bright Kuiper Belt objects and Centaurs were observed to systematically monitor them for possible short and long term light variations due to rotational, phase angle, binary and cometary effects. About 29% display significant (≥0.15 magnitude range) lightcurves. Statistically, the trans-Neptunian objects are less spherical than their main-belt asteroid counterparts, indicating structural differences or a higher specific angular momentum perhaps resulting from the formation epoch. Short-term lightcurves of KBOs were observed to resemble rotationally distorted, low density rubble piles, contact binaries and albedo effects. By correcting for the effects of projection, it is estimated that the fraction of contact binaries in the Kuiper Belt is at least ∼10% to 20%.;Phase darkening for 13 Kuiper Belt objects in the 0 to 2 degree phase angle range were measured. Unlike Pluto, the measured values show steep linear slopes indicating backscatter from low albedo porous surface materials.;Deep wide-field surveys of Mars, Jupiter, Saturn, Uranus and Neptune have discovered 46 new outer satellites of Jupiter, 1 of Saturn, 2 of Uranus and 1 of Neptune. Through these surveys it is shown that the giant planets all have statistically similar irregular satellite population densities, size distributions and orbital structures independent of their mass or formation scenario.
Keywords/Search Tags:Kuiper belt, Outer, Centaur
Related items