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CMA presents "Planet Nine from Outer Space"

Tuesday, April 5, 2016
4:40pm to 6:00pm
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Konstantin Batygin, Assistant Professor of Planetary Sciences, Geological and Planetary Sciences, Caltech,

What if we discovered that our solar system contains a planet no one ever knew about before?

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 are not randomly oriented, and like a jigsaw puzzle, show a lot of large-scale structure when viewed collectively. Much of this structure can be attributed to periodic gravitational pulls exerted by Neptune as it traverses its orbit in a clockwork fashion. However, novel observations that have surfaced over the last two years have revealed a feature of the Kuiper belt that has, despite numerous efforts, eluded explanation.

All Kuiper belt objects with orbital periods longer than 7,000 years have orbits that are physically aligned. Statistically, the chances of such alignment being a coincidence are smaller than a hundredth of a percent. What sculpts this alignment and how is it preserved? In this talk, Konstantin Batygin 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. In addition to accounting for the observed grouping of trajectories, the existence of such a planet naturally explains other, seemingly unrelated dynamical features of the solar system. 

Professor Batygin and his colleague Michael Brown described their findings in a recent article published in the Astronomical Journal. Professor Batygin's primary research interests lie in understanding our solar system's place within its galactic context. He is on the 2015 Forbes list of 30 scientists under 30 who are changing the world.

This event is free. All members of the Campus and JPL communities and retirees are welcome. For the JPL talk, because of security requirements, individuals without JPL badges must have a Laboratory employee or resident affiliate submit a visitor request and be their escort. Foreign-person visitor requests must be submitted at least four working days before the event; U.S.-person visitor requests must be submitted at least two working days before the event. For more information, contact Athena Castro at (626) 395-6163 or [email protected]. Or email [email protected].

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For more information, please contact Athena Castro by phone at (626) 395-6163.