Planet Nine From Outer Space

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At the outskirts of the solar system, beyond the orbit of Neptune, lies an expansive field of icy debris known as the Kuiper belt. The orbits of the individual asteroid-like bodies within the Kuiper belt trace out highly elongated elliptical paths, requiring hundreds to thousands of years to complete a single revolution around the sun.

Although the majority of the Kuiper belt’s dynamical structure can be understood within the framework of the known eight-planet solar system, bodies with orbital periods longer than about 4,000 years exhibit a peculiar orbital alignment that eludes explanation. What sculpts this alignment and how is it preserved?

In this talk, I will argue that the observed clustering of Kuiper belt orbits can be maintained by a distant, eccentric, Neptune-like planet, whose orbit lies in approximately the same plane as those of the distant Kuiper belt objects, but is anti-aligned with respect to those of the small bodies. In addition to accounting for the observed grouping of orbits, the existence of such a planet naturally explains other, seemingly unrelated dynamical features of the solar system.

About the Speaker

Forbes named professor Konstantin Batygin the “next physics rock star” in its 2015 list of “30 Under 30: Young Scientists Who Are Changing the World.” He received his bachelor’s degree in physics from University of California, Santa Cruz, in 2008, before pursuing graduate studies at California Institute of Technology.

Batygin has authored over 70 scientific publications,, His research has been featured on Nature, as well as the front cover of Scientific American.

Prior to joining the faculty at California Institute of Technology in 2014, Batygin was a visiting scientist at Observatoire de la Côte d'Azur, in Nice, France, and an ITC postdoctoral fellow at Harvard University. When not doing science, he moonlights as the lead singer in the rock band The Seventh Season.


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    A. Maureen Rouhi
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