Thursday, December 8, 2022, 16:00
WBGB/019
Konstantin Batygin, Caltech
Abstract:
Over the course of the past two decades, observational surveys have
unveiled the intricate orbital structure of the Kuiper Belt, a field of
icy bodies orbiting the Sun beyond Neptune. In addition to a host of
readily-predictable orbital behavior, the emerging census of
trans-Neptunian objects appears to display dynamical phenomena that
cannot be explained by interactions with the known eight-planet Solar
System alone. Specifically, the observed physical clustering of orbits
with semi-major axes in excess of ∼ 250 AU, the detachment of
perihelia of select Kuiper belt objects from Neptune, as well as the
dynamical origin of highly inclined/retrograde long-period orbits remain
elusive within the context of the classical view of the Solar System.
This newly outlined dynamical architecture of the distant solar system
points to the existence of a planet with mass M9 ∼
5M♁ on a moderately inclined orbit with a semi-major axis
a9 ∼ 400 – 800 AU and eccentricity e9 ∼
0.4 – 0.6. In this talk, I will review the observational motivation,
dynamical constraints, and prospects for the detection of this proposed
object known as Planet Nine.