A planet within the debris disk around the pre-main-sequence star AU Microscopii

TL;DR

This paper reports the discovery of a transiting planet, AU Mic b, orbiting the nearby young star AU Microscopii, providing valuable insights into planet formation within a debris disk environment.

Contribution

It presents the first detection of a planet transiting a star with a spatially resolved debris disk, offering a unique case to study planet formation and evolution.

Findings

AU Mic b has an 8.46-day orbit and a radius of 0.4 Jupiter radii.

The planet's mass is constrained to less than 0.18 Jupiter masses.

The system allows testing of planet formation models in debris disk environments.

Abstract

AU Microscopii (AU Mic) is the second closest pre main sequence star, at a distance of 9.79 parsecs and with an age of 22 million years. AU Mic possesses a relatively rare and spatially resolved3 edge-on debris disk extending from about 35 to 210 astronomical units from the star, and with clumps exhibiting non-Keplerian motion. Detection of newly formed planets around such a star is challenged by the presence of spots, plage, flares and other manifestations of magnetic activity on the star. Here we report observations of a planet transiting AU Mic. The transiting planet, AU Mic b, has an orbital period of 8.46 days, an orbital distance of 0.07 astronomical units, a radius of 0.4 Jupiter radii, and a mass of less than 0.18 Jupiter masses at 3 sigma confidence. Our observations of a planet co-existing with a debris disk offer the opportunity to test the predictions of current models of planet formation and evolution.