Astronomers capture 'vampire' star sucking the life out of a victim

In 2020 a team of astronomers reported locating the closest black hole system at 1,000 light-years from Earth, but fellow researchers contested the results of the study and teamed up to produce a new study together.

The international team of astronomy researchers has published a new paper in Astronomy & Astrophysics that details the HR 6818 system with the European Southern Observatory's Very Large Telescope. According to the paper, the HR 6818 system isn't a triple system that consists of one star orbiting a black hole every 40 days and a second star orbiting much wider as it was originally thought. It is actually a system that features two stars orbiting each other with no black hole.

The team used two of the VLT's instruments called GRAVITY and the Multi-Unit Spectroscopic Explorer (MUSE), and with the results, were able to conclude that HR 6819 is a binary system that features two stars and no black hole. The reasoning for the miscategorization is that astronomers originally observed the system when one of the stars was ripping the atmosphere off of its companion star, which is described as being much like a vampire drawing blood from its victim.

"We agreed that there were two sources of light in the system, so the question was whether they orbit each other closely, as in the stripped-star scenario, or are far apart from each other, as in the black hole scenario," said team lead Thomas Rivinius, a Chile-based ESO astronomer and co-author of a new paper.

The results "confirmed that there was no bright companion in a wider orbit," and "was able to resolve two bright sources separated by only one-third of the distance between the Earth and the Sun. These data proved to be the final piece of the puzzle, and allowed us to conclude that HR 6819 is a binary system with no black hole," said Abigail Frost, KU Leuven researcher and lead author of the study.

"Our best interpretation so far is that we caught this binary system in a moment shortly after one of the stars had sucked the atmosphere off its companion star," said Julia Bodensteiner, KU Leuven researcher and coauthor, in the statement.

"Catching such a post-interaction phase is extremely difficult as it is so short" and that HR 6819 "presents a perfect candidate to study how this vampirism affects the evolution of massive stars," added Frost.