Mass, Density, and Formation Constraints in the Compact, Sub-Earth Kepler-444 System including Two Mars-Mass Planets

Sean M. Mills, Daniel C. Fabrycky
(Submitted on 9 Mar 2017)

Kepler-444 is a five planet system around a host-star approximately 11 billion years old. The five transiting planets all have sub-Earth radii and are in a compact configuration with orbital periods between 3 and 10 days. Here we present a transit-timing analysis of the system using the full Kepler data set in order to determine the masses of the planets. Two planets, Kepler-444 d (Md=0.036+0.065−0.020M⊕) and Kepler-444 e (Me=0.034+0.059−0.019M⊕), have confidently detected masses due to their proximity to resonance which creates transit timing variations. The mass ratio of these planets combined with the magnitude of possible star-planet tidal effects suggests that smooth disk migration over a significant distance is unlikely to have brought the system to its currently observed orbital architecture without significant post-formation perturbations.

Comments:    Accepted for publication in ApJL
Subjects:    Earth and Planetary Astrophysics (astro-ph.EP)
Cite as:    arXiv:1703.03417 [astro-ph.EP] (or arXiv:1703.03417v1 [astro-ph.EP] for this version)
Submission history
From: Sean M. Mills
[v1] Thu, 9 Mar 2017 19:00:06 GMT (1102kb)
https://arxiv.org/abs/1703.03417