The recent discovery of a staggering diversity of planets beyond the Solar
System has brought with it a greatly expanded search space for habitable
worlds. The Kepler exoplanet survey has revealed that most planets in our
interstellar neighborhood are larger than Earth and smaller than Neptune.
Collectively termed super-Earths and mini-Neptunes, some of these planets may
have the conditions to support liquid water oceans, and thus Earth-like
biology, despite differing in many ways from our own planet. In addition to
their quantitative abundance, super-Earths are relatively large and are thus
more easily detected than true Earth twins. As a result, super-Earths represent
a uniquely powerful opportunity to discover and explore a panoply of
fascinating and potentially habitable planets in 2020 - 2030 and beyond.Comment: Science white paper submitted to the 2020 Astronomy and Astrophysics
Decadal Surve
