Forming the Kuiper Cliff
When
Where
Dr. Ann-Marie Madigan
Associate Professor of Astrophysics
University of Colorado, Boulder
The Solar System's Kuiper Belt has an observed ‘cliff’ at 48-50 AU: a sharp drop in surface density of bodies unpredicted by theory. In this talk, I will try to explain the Kuiper Cliff via a new dynamical mechanism. Hypothesizing that the Kuiper Belt once extended far beyond its current edge, I’ll show that gravitational torques between the circular orbits of outer Kuiper Belt members and those scattered outward onto eccentric orbits by the giant planets can drive the Kuiper Belt objects onto highly elliptical paths. At closest approach to the Sun, these bodies suffer strong gravitational encounters with the giant planets and ultimately scatter out of the Solar System. This new mechanism may also naturally explain the halt to Neptune's outward migration early in the Solar System's evolution.