The next frontier in exoplanet science: Imaging our neighbouring planetary systems

TL;DR

High-contrast imaging with upcoming Extremely Large Telescopes will enable detailed study of nearby rocky exoplanets, surpassing current transmission and eclipse spectroscopy limitations due to stellar noise.

Contribution

This paper advocates for the use of high-contrast imaging with ELTs as the next major step in characterising small, temperate exoplanets around nearby stars, highlighting future observational prospects.

Findings

ELTs will enable imaging of rocky planets around red dwarfs.

Upcoming instruments like PCS and GmagAO-X will operate by 2040.

Ground-based methods will complement space missions in exoplanet research.

Abstract

Transmission and eclipse spectroscopy have been invaluable tools for the characterisation of extrasolar planet atmospheres. While they will continue to provide many new insights and discoveries in the decade(s) to come, these methods are running up against sources of stellar noise from stellar surface inhomogeneities and variability. In this white paper we discuss how the next steps in the characterisation of small, temperate rocky planets requires high-contrast imaging, making the planetary systems around our closest neighbouring stars the new frontier in exoplanet science. The Extremely Large Telescopes (ELTs) will be at the forefront of this quest. The Planetary Camera and Spectrograph (PCS) on ESO's ELT and GmagAO-X on the GMT are planned to become operational in the 2035-2040 time-frame, allowing the characterisation of up to dozen(s) of rocky planets around nearby red dwarf stars. We discuss what role there will be still to play for ground-based exoplanet characterisation in the era of the space-borne Habitable Worlds Observatory and LIFE missions.