IUCAA researchers discover rare white dwarf–red giant star system

An international team led by IUCAA researchers discovered the first confirmed symbiotic accreting system in the Magellanic Bridge, named eRASSU J043115.8−711730 (J0431−71), consisting of a white dwarf and a red giant.

The white dwarf pulls gas from the red giant as it expands and contracts in a cycle of about 500 days, producing X-rays detected by the German eROSITA telescope.

The finding used data from eROSITA's second public data release (DR2), which catalogued nearly two million X-ray sources, and was confirmed with Gaia, SALT, and OGLE observations.

The Magellanic Bridge is a stream of gas and stars connecting the Large and Small Magellanic Clouds, formed by their gravitational interaction.

The discovery provides new clues about compact star evolution in interacting galaxies.