Ultraviolet observations of atmospheric escape in exoplanets with the Habitable Worlds Observatory

TL;DR

This paper discusses the use of ultraviolet transit spectroscopy with the Habitable Worlds Observatory to study atmospheric escape in exoplanets, aiding the search for Earth-like worlds.

Contribution

It proposes developing UV spectrograph technology for detailed atmospheric analysis of exoplanets to understand their evolution and habitability.

Findings

UV observations can reveal atmospheric escape processes

Potential to identify Earth-like atmospheres

Techniques for atmospheric retention assessment

Abstract

Among the many recommendations of the Decadal Survey on Astronomy and Astrophysics 2020, we found that a priority area of research is to pave the pathways towards finding and characterizing habitable worlds. In this context, we aim to understand how planetary systems evolve through atmospheric escape, and develop techniques to identify potentially Earth-like worlds. Using the ultraviolet (UV) capabilities of the Habitable Worlds Observatory, we can use transit spectroscopy observations to determine what processes drive the evolution of exoplanets, how well can small exoplanets retain atmospheres, and search for Earth-like atmospheres. We advocate the development of a UV spectrograph that is capable of moderate- to high-resolution spectroscopy of point sources, access to key spectral features between 1000 and 3000 Angstrom, and UV detectors that are resilient to high count rates.