Evidence for a sub-jovian planet in the young TWA7 disk

TL;DR

This study used JWST/MIRI's high sensitivity to detect a sub-Jupiter mass planet in the debris disk of TWA 7, providing direct evidence linking disk features to planetary presence.

Contribution

First direct detection of a planet in a debris disk using JWST, confirming the role of planets in shaping disk structures.

Findings

Detected a ~0.3 MJ planet at 52 au from TWA 7

Planet's position explains observed disk features

Demonstrated JWST's capability for planet detection in debris disks

Abstract

Planets are thought to form from dust and gas in protoplanetary disks, and debris disks are the remnants of planet formation. Aged a few Myr up to a few Gyr, debris disks have lost their primordial gas, and their dust is produced by steady-state collisions between larger, rocky bodies. Tens of debris disks, with sizes of tens, sometimes hundreds of au, have been resolved with high spatial resolution, high contrast imagers at optical/near-IR or (sub)-millimeter interferometers. They commonly show cavities, ring-like structures, and gaps, which are often regarded as indirect signatures of the presence of planets that gravitationally interact with unseen planetesimals. However, no planet responsible for these features has been detected yet, probably because of the limited sensitivity (typically 2-10 MJ) of high contrast imaging instruments prior to JWST. We have used the unprecedented sensitivity of JWST/MIRI in the thermal IR to search for such planets in the disk of the ~ 6.4 Myr old star TWA 7. With its pole-on orientation, this three-ring debris disk is indeed ideally suited for such a detection. We unambiguously detected a source 1.5 arsec from the star, that is best interpreted as a cold, sub-Jupiter mass planet. Its estimated mass (~ 0.3 MJ) and position (~ 52 au, de-projected) can thoroughly account for the main disk structures.