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arXiv · 1709.01957

A System of Three Super Earths Transiting the Late K-Dwarf GJ 9827 at Thirty Parsecs

Joseph E. Rodriguez·Andrew Vanderburg·Jason D. Eastman·Andrew W. Mann·Ian J. M. Crossfield·David R. Ciardi·David W. Latham·Samuel N. Quinn
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Abstract

We report the discovery of three small transiting planets orbiting GJ 9827, a bright (K = 7.2) nearby late K-type dwarf star. GJ 9827 hosts a $1.62\pm0.11$ $R_{\rm \oplus}$ super Earth on a 1.2 day period, a $1.269^{+0.087}_{-0.089}$ $R_{\rm \oplus}$ super Earth on a 3.6 day period, and a $2.07\pm0.14$ $R_{\rm \oplus}$ super Earth on a 6.2 day period. The radii of the planets transiting GJ 9827 span the transition between predominantly rocky and gaseous planets, and GJ 9827 b and c fall in or close to the known gap in the radius distribution of small planets between these populations. At a distance of 30 parsecs, GJ 9827 is the closest exoplanet host discovered by K2 to date, making these planets well-suited for atmospheric studies with the upcoming James Webb Space Telescope. The GJ 9827 system provides a valuable opportunity to characterize interior structure and atmospheric properties of coeval planets spanning the rocky to gaseous transition.

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Joseph E. Rodriguez, Andrew Vanderburg, Jason D. Eastman, Andrew W. Mann, Ian J. M. Crossfield, David R. Ciardi, David W. Latham, Samuel N. Quinn. 2017-09-06. A System of Three Super Earths Transiting the Late K-Dwarf GJ 9827 at Thirty Parsecs. https://doi.org/10.3847/1538-3881%2Faaa292

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