Atmospheric Escape and the Evolution of Close-In Exoplanets

By J. Owen. Annual Review of Earth and Planetary Science, 2018

203 citations recorded by the source corpus.

Exoplanets with substantial hydrogen/helium atmospheres have been discovered in abundance, many residing extremely close to their parent stars. The extreme irradiation levels that these atmospheres experience cause them to undergo hydrodynamic atmospheric escape. Ongoing atmospheric escape has been observed to be occurring in a few nearby exoplanet systems through transit spectroscopy both for hot Jupiters and for lower-mass super-Earths and mini-Neptunes. Detailed hydrodynamic calculations that incorporate radiative transfer and ionization chemistry are now common in one-dimensional models, and multidimensional calculations that incorporate magnetic fields and interactions with the interstellar environment are cutting edge. However, comparison between simulations and observations remains very limited. While hot Jupiters experience atmospheric escape, the mass-loss rates are not high enough to affect their evolution. However, for lower-mass planets, atmospheric escape drives and controls their evolution, sculpting the exoplanet population that we observe today. ▪ Observations of some exoplanets have detected atmospheric escape driven by hydrodynamic outflows, causing the exoplanets to lose mass over time. ▪ Hydrodynamic simulations of atmospheric escape are approaching the sophistication required to compare them directly to observations. ▪ Atmospheric escape sculpts sharp features into the exoplanet population that we can observe today; these features have recently been detected.

Subfields: Astronomy and Astrophysics, Instrumentation, Statistical and Nonlinear Physics

View Paper: https://www.semanticscholar.org/paper/3006349155fc14a4f7b8a1a2f85b3f4f23244221

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. D. Huber
2. J. V. van Saders
3. T. Berger
4. E. Gaidos
5. N. Madhusudhan
6. L. Weiss
7. A. Mann
8. Jon Fortney

In Instrumentation

1. J. V. van Saders
2. D. Huber
3. E. Gaidos
4. T. Berger
5. N. Madhusudhan
6. L. Weiss
7. D. Deming
8. R. MacDonald

In Statistical and Nonlinear Physics

1. J. V. van Saders
2. T. Berger
3. N. Madhusudhan
4. E. Gaidos
5. D. Huber
6. L. Weiss
7. Leslie A. Rogers

Citations in the corpus

• Exoplanetary Atmospheres: Key Insights, Challenges, and Prospects (2019, background): “A comprehensive review of theoretical developments in atmospheric escape processes can be found in (199).”
• The Gaia–Kepler Stellar Properties Catalog. II. Planet Radius Demographics as a Function of Stellar Mass and Age (2020, background): “More theoretical and observational work is required to evaluate the composition of these atmospheres (Owen 2019), and we caution that these inferences are tentative, especially because of the small number of planets contained in the old and young low-flux (49 and 44 planets, respectively) and old…”