JWST Directly Images Giant Planet Candidates Around Two Metal-Polluted White Dwarf Stars

TL;DR

This paper reports the discovery of two giant planet candidates around metal-rich white dwarfs using JWST, suggesting that such planets can survive stellar evolution and may be linked to white dwarf metal pollution.

Contribution

First direct imaging of giant planet candidates around white dwarfs that are similar in age and separation to solar system giants, indicating planet survival after stellar evolution.

Findings

Candidates have masses 1-7 Jupiter Masses.

Low probability (~1/3000) of false positives.

Potential link between giant planets and white dwarf metal pollution.

Abstract

We report the discovery of two directly imaged, giant planet candidates orbiting the metal-rich DAZ white dwarfs WD 1202-232 and WD 2105-82. JWST's Mid-Infrared Instrument (MIRI) data on these two stars show a nearby resolved source at a projected separation of 11.47 and 34.62 au, respectively. Assuming the planets formed at the same time as their host stars, with total ages of 5.3 and 1.6Gyr, the MIRI photometry is consistent with giant planets with masses about 1-7 Jupiter Masses. The probability of both candidates being false positives due to red background sources is approximately 1 in 3000. If confirmed, these would be the first directly imaged planets that are similar in both age and separation to the giant planets in our own solar system, and they would demonstrate that widely separated giant planets like Jupiter survive stellar evolution. Giant planet perturbers are widely used to explain the tidal disruption of asteroids around metal-polluted white dwarfs. Confirmation of these two planet candidates with future MIRI imaging would provide evidence that directly links giant planets to metal pollution in white dwarf stars.