Large Impacts around a Solar Analog Star in the Era of Terrestrial Planet Formation

TL;DR

This paper reports the real-time detection of a debris-producing impact around a young solar analog star, providing direct observational insights into the violent processes involved in terrestrial planet formation.

Contribution

It presents the first real-time observation of a planetary impact in the terrestrial zone, highlighting the potential of time-domain studies in understanding planet formation.

Findings

Detected a brightening and decay of debris disk consistent with a planetary impact.

Observed quasi-periodic modulations in disk flux over a year.

Confirmed impact-produced dust cloud formation and evolution.

Abstract

The final assembly of terrestrial planets occurs via massive collisions, which can launch copious clouds of dust that are warmed by the star and glow in the infrared. We report the real-time detection of a debris-producing impact in the terrestrial planet zone around a 35-million year-old solar analog star. We observed a substantial brightening of the debris disk at 3-5 {\mu}m, followed by a decay over a year, with quasi-periodic modulations of the disk flux. The behavior is consistent with the occurrence of a violent impact that produced vapor out of which a thick cloud of silicate spherules condensed that were ground into dust by collisions. These results demonstrate how the time domain can become a new dimension for the study of terrestrial planet formation.