History and Habitability of the LP 890-9 Planetary System
Abstract
We present numerous aspects of the evolution of the LP 890-9 (SPECULOOS-2/TOI-4306) planetary system, focusing on the likelihood that planet c can support life. We find that the host star reaches the main sequence in 1 Gyr and that planet c lies close to the inner boundary of the habitable zone. We find the magma ocean stage can last up to 50 Myr, remove 8 Earth-oceans of water, and leave up to 2000 bars of oxygen in the atmosphere. However, if the planet forms with a hydrogen envelope as small as 0.1 Earth-masses, no water will be lost during the star's pre-main sequence phase from thermal escape processes. We find that the planets are unlikely to be in a 3:1 mean motion resonance and that both planets tidally circularize within 0.5 Gyr when tidal dissipation is held constant. However, if tidal dissipation is a function of mantle temperature and rheology, then we find that planet c's orbit may require more than 7 Gyr to circularize, during which time tidal heating may reach hundreds of terawatts. We thus conclude that the habitability of planet c depends most strongly on the initial volatile content and internal properties, but no data yet preclude the viability of an active biosphere on the planet.
Keywords
Cite
@article{arxiv.2412.02743,
title = {History and Habitability of the LP 890-9 Planetary System},
author = {Rory Barnes and Laura N. R. do Amaral and Jessica Birky and Ludmila Carone and Peter Driscoll and Joseph R. Livesey and David Graham and Juliette Becker and Kaiming Cui and Martin Schlecker and Rodolfo Garcia and Megan Gialluca and Arthur Adams and MD Redyan Ahmed and Paul Bonney and Wynter Broussard and Chetan Chawla and Mario Damasso and William C. Danchi and Russell Deitrick and Elsa Ducrot and Emeline F. Fromont and Brandt A. L. Gaches and Sakshi Gupta and Michelle L. Hill and James A. G. Jackman and Estelle M. Janin and Mikolaj Karawacki and Matheus Daniel Koren and Roberto La Greca and Michaela Leung and Arturo Miranda-Rosete and Michael Kent A. Olohoy and Cecelia Ngo and Daria Paul and Chandan Kumar Sahu and Debajyoti Basu Sarkar and Mohammad Afzal Shadab and Edward W. Schwieterman and Melissa Sedler and Katie Texeira and Allona Vazan and Karen N. Delgado Vega and Rohit Vijayakumar and Jonathan T. Wojack},
journal= {arXiv preprint arXiv:2412.02743},
year = {2024}
}
Comments
16 pages, 9 figures, accepted to PSJ