Maximizing the sensitivity of ELT to habitable worlds with a space-based starshade

TL;DR

Combining the Extremely Large Telescope (ELT) with a space-based starshade could significantly enhance the ability to detect and study Earth-like habitable exoplanets, addressing key questions about life's prevalence in the universe.

Contribution

This paper proposes a novel observational strategy integrating ELT with a space-based starshade to improve contrast and enable detection of Earth analogs.

Findings

ELT combined with a starshade can observe tens of Earth-like planets.

This approach surpasses current contrast limitations for habitable-zone exoplanets.

Synergy between ground-based and space-based instruments enhances exoplanet science.

Abstract

The ELT will provide groundbreaking science across a wide range of areas, including small habitable-zone exoplanets; however, true Earth analogs in the habitable zones of Sun-like stars are generally beyond the reach even of the ELT, due to the extreme contrast ratio and small angular separation between the planet and star. Here, we note that the combination of ELT and a space-based starshade would provide the contrast needed to observe potentially tens of Earth analogs, as well as other planets. This would yield the scientific basis needed for addressing central scientific questions regarding the frequency and distribution of habitability and life in the Universe. The huge aperture of ELT, combined with a contrast otherwise only reachable in space, opens up scientific avenues that are unmatched by any other existing or foreseen facility. ESO could conceivably collaborate with ESA (and others) to facilitate a starshade mission suitable for synergy with the ELT, as well as to prepare the ELT instrumentation in order to maximize its potential for synergy with a starshade.