Document Type
Article
Publication Date
1-1-2020
Published In
Monthly Notices Of The Royal Astronomical Society
Abstract
We report the discovery of the 1.008-d, ultrashort period (USP) super-Earth HD 213885b (TOI-141b) orbiting the bright (V = 7.9) star HD 213885 (TOI-141, TIC 403224672), detected using photometry from the recently launched TESS mission. Using FEROS, HARPS, and CORALIE radial velocities, we measure a precise mass of 8.8 ± 0.6 M⊕ for this 1.74 ± 0.05 R⊕ exoplanet, which provides enough information to constrain its bulk composition – similar to Earth’s but enriched in iron. The radius, mass, and stellar irradiation of HD 213885b are, given our data, very similar to 55 Cancri e, making this exoplanet a good target to perform comparative exoplanetology of short period, highly irradiated super-Earths. Our precise radial velocities reveal an additional 4.78-d signal which we interpret as arising from a second, non-transiting planet in the system, HD 213885c, whose minimum mass of 19.9 ± 1.4 M⊕ makes it consistent with being a Neptune-mass exoplanet. The HD 213885 system is very interesting from the perspective of future atmospheric characterization, being the second brightest star to host an USP transiting super-Earth (with the brightest star being, in fact, 55 Cancri). Prospects for characterization with present and future observatories are discussed.
Keywords
techniques: photometric, techniques: radial velocities, planets and satellites: detection, planets and satellites: fundamental parameters, planets and satellites: individual: TOI-141, TIC 403224672, HD213885
Recommended Citation
N. Espinoza et al.
(2020).
"HD 213885b: A Transiting 1-D-Period Super-Earth With An Earth-Like Composition Around A Bright (V = 7.9) Star Unveiled By TESS".
Monthly Notices Of The Royal Astronomical Society.
Volume 491,
Issue 2.
2982-2999.
DOI: 10.1093/mnras/stz3150
https://works.swarthmore.edu/fac-physics/409
Comments
This article has been published in Monthly Notices Of The Royal Astronomical Society. © 2019 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.