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The Planet Nine hypothesis

Brown, Michael E. (2019) The Planet Nine hypothesis. Physics Today, 72 (3). pp. 70-71. ISSN 0031-9228. doi:10.1063/PT.3.4172.

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In 1820 Alexis Bouvard, the director of the Paris Observatory, made what could have been a huge discovery. The planet Uranus, whose position he had tracked back 130 years in old star catalogs, didn’t quite go around the Sun the way that he predicted it should. It traveled along its elliptical orbit as expected, but sometimes the old observations suggested it was a little ahead of its predicted position and sometimes a little behind. Bouvard might have realized that there was something beyond Uranus, but instead he was convinced the old star catalogs were simply wrong.

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Brown, Michael E.0000-0002-8255-0545
Additional Information:© 2019 American Institute of Physics.
Group:Astronomy Department
Issue or Number:3
Record Number:CaltechAUTHORS:20190313-160836642
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:93794
Deposited By: Tony Diaz
Deposited On:13 Mar 2019 23:21
Last Modified:16 Nov 2021 17:00

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