Astronomers have painted their best picture yet of an RV Tauri variable, a rare type of stellar binary where two stars – one approaching the end of its life – orbit within a sprawling disk of dust. Their 130-year dataset spans the widest range of light yet collected for one of these systems, from radio to X-rays.

“There are only about 300 known RV Tauri variables in the Milky Way galaxy,” said Laura Vega, a recent doctoral recipient at Vanderbilt University in Nashville, Tennessee. “We focused our study on the second brightest, named U Monocerotis, which is now the first of these systems from which X-rays have been detected.”

A paper describing the findings, led by Vega, was published in The Astrophysical Journal.