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arXiv · 2007.10339

The Case for an Early Solar Binary Companion

Amir Siraj·Abraham Loeb
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Abstract

We show that an equal-mass, temporary binary companion to the Sun in the solar birth cluster at a separation of $\sim 10^3 \; \mathrm{\; AU}$ would have increased the likelihood of forming the observed population of outer Oort cloud objects and of capturing Planet Nine. In particular, the discovery of a captured origin for Planet Nine would favor our binary model by an order of magnitude relative to a lone stellar history. Our model predicts an overabundance of dwarf planets, discoverable by LSST, with similar orbits to Planet Nine, which would result from capture by the stellar binary.

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Amir Siraj, Abraham Loeb. 2020-07-20. The Case for an Early Solar Binary Companion. https://doi.org/10.3847/2041-8213%2Fabac66

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