GJ 832c: A super-earth in the habitable zone

TL;DR

This paper reports the discovery of GJ 832c, a super-Earth near the habitable zone of an M dwarf, using radial velocity measurements, highlighting its potential atmospheric characteristics and system similarities to our Solar System.

Contribution

First detection of a super-Earth in the habitable zone of GJ 832 using combined radial velocity data from three telescopes.

Findings

GJ 832c has a 35.68-day orbit with a minimum mass of 5.4 Earth masses.

GJ 832c's orbit is low-eccentricity, near the habitable zone edge.

The planet likely has a thick atmosphere, possibly making it a super-Venus.

Abstract

We report the detection of GJ 832c, a super-Earth orbiting near the inner edge of the habitable zone of GJ 832, an M dwarf previously known to host a Jupiter analog in a nearly-circular 9.4-year orbit. The combination of precise radial-velocity measurements from three telescopes reveals the presence of a planet with a period of 35.68+/-0.03 days and minimum mass (m sin i) of 5.4+/-1.0 Earth masses. GJ 832c moves on a low-eccentricity orbit (e=0.18+/-0.13) towards the inner edge of the habitable zone. However, given the large mass of the planet, it seems likely that it would possess a massive atmosphere, which may well render the planet inhospitable. Indeed, it is perhaps more likely that GJ 832c is a "super-Venus," featuring significant greenhouse forcing. With an outer giant planet and an interior, potentially rocky planet, the GJ 832 planetary system can be thought of as a miniature version of our own Solar system.