Habitable Zones & Global Climate

On The Hydrosphere Stability of TESS Targets: Applications to 700 d, 256 b, and 203 b

By Keith Cowing
March 2, 2022
Filed under
On The Hydrosphere Stability of TESS Targets: Applications to 700 d, 256 b, and 203 b
Figure adapted from Kanodia et al. (2019) highlighting the nonparametric fit for mass given radius used in this work shown in red. The accompanying fit for radius given mass is also shown in blue. The mean of the fits is shown as a dark line and the shaded regions show the 16% and 84% quantiles for the conditional distributions. Data used in this fitting are from the Kepler dataset.

A main determinant of the habitability of exoplanets is the presence of stable liquid surface water. In an era of abundant possible targets, the potential to find a habitable world remains a driving force in prioritization.

We present here a data-forward method to investigate the likelihood of a stable hydrosphere on the timescales of the formation of life, 1 Gyr, and beyond. As our primary application, we use this method to examine the potential hydrospheres of TESS Objects of Interest 700 d, 256 b, and 203 b. We first present our selection criteria, which is based on an implementation of the Earth Similarity Index, as well as the results of an initial investigation into the desiccation of the targets, which reveals that TOI 203 b is almost certainly desiccated based on TESS observations. We then describe the characterization of the remaining targets and their host stars from 2MASS, Gaia, and TESS data and the derivation of sampled probability distributions for their parameters.

Following this, we describe our process of simulating the desiccation of the targets hydrospheres using the Virtual Planet Simulator, VPLanet, with inputs directly linked to the previously derived probability distributions. We find that 50.86 percent of the likely cases for TOI 700 d are desiccated and no modeled cases for TOI 256 b are without water. In addition, we calculate the remaining water inventory for the targets, the percentage of cases that are continuing to lose water, and the rate at which these cases are losing water.

Paul Bonney (1 and 2), Julia Kennefick (1) ((1) Corresponding author: [email protected], (2) Department of Physics, University of Arkansas)

Comments: 17 pages, 6 figures, 3 tables. Submitted to The Planetary Science Journal (2/28/22)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2203.00222 [astro-ph.EP] (or arXiv:2203.00222v1 [astro-ph.EP] for this version)
Submission history
From: Paul Bonney
[v1] Tue, 1 Mar 2022 04:17:38 UTC (595 KB)

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻