A Giant Planet Candidate Transiting a White Dwarf
Abstract
Astronomers have discovered thousands of planets outside the solar system, most of which orbit stars that will eventually evolve into red giants and then into white dwarfs. During the red giant phase, any close-orbiting planets will be engulfed by the star, but more distant planets can survive this phase and remain in orbit around the white dwarf. Some white dwarfs show evidence for rocky material floating in their atmospheres, in warm debris disks, or orbiting very closely, which has been interpreted as the debris of rocky planets that were scattered inward and tidally disrupted. Recently, the discovery of a gaseous debris disk with a composition similar to ice giant planets demonstrated that massive planets might also find their way into tight orbits around white dwarfs, but it is unclear whether the planets can survive the journey. So far, the detection of intact planets in close orbits around white dwarfs has remained elusive. Here, we report the discovery of a giant planet candidate transiting the white dwarf WD 1856+534 (TIC 267574918) every 1.4 days. The planet candidate is roughly the same size as Jupiter and is no more than 14 times as massive (with 95% confidence). Other cases of white dwarfs with close brown dwarf or stellar companions are explained as the consequence of common-envelope evolution, wherein the original orbit is enveloped during the red-giant phase and shrinks due to friction. In this case, though, the low mass and relatively long orbital period of the planet candidate make common-envelope evolution less likely. Instead, the WD 1856+534 system seems to demonstrate that giant planets can be scattered into tight orbits without being tidally disrupted, and motivates searches for smaller transiting planets around white dwarfs.
Keywords
Cite
@article{arxiv.2009.07282,
title = {A Giant Planet Candidate Transiting a White Dwarf},
author = {Andrew Vanderburg and Saul A. Rappaport and Siyi Xu and Ian Crossfield and Juliette C. Becker and Bruce Gary and Felipe Murgas and Simon Blouin and Thomas G. Kaye and Enric Palle and Carl Melis and Brett Morris and Laura Kreidberg and Varoujan Gorjian and Caroline V. Morley and Andrew W. Mann and Hannu Parviainen and Logan A. Pearce and Elisabeth R. Newton and Andreia Carrillo and Ben Zuckerman and Lorne Nelson and Greg Zeimann and Warren R. Brown and René Tronsgaard and Beth Klein and George R. Ricker and Roland K. Vanderspek and David W. Latham and Sara Seager and Joshua N. Winn and Jon M. Jenkins and Fred C. Adams and Björn Benneke and David Berardo and Lars A. Buchhave and Douglas A. Caldwell and Jessie L. Christiansen and Karen A. Collins and Knicole D. Colón and Tansu Daylan and John Doty and Alexandra E. Doyle and Diana Dragomir and Courtney Dressing and Patrick Dufour and Akihiko Fukui and Ana Glidden and Natalia M. Guerrero and Xueying Guo and Kevin Heng and Andreea I. Henriksen and Chelsea X. Huang and Lisa Kaltenegger and Stephen R. Kane and John A. Lewis and Jack J. Lissauer and Farisa Morales and Norio Narita and Joshua Pepper and Mark E. Rose and Jeffrey C. Smith and Keivan G. Stassun and Liang Yu},
journal= {arXiv preprint arXiv:2009.07282},
year = {2020}
}
Comments
50 pages, 12 figures, 2 tables. Published in Nature on Sept. 17, 2020. The final authenticated version is available online at: https://www.nature.com/articles/s41586-020-2713-y