Star on the run; said to be leaving Milky Way at record speeds


An unbound star dubbed US708 is on the run at staggering speeds of 1,200 km/s – enough to escape the shackles of the Milky Way.

US708 is believed to have once been part of a double-star solar system, which also included a massive white dwarf star and it is the fastest such object that has been recorded in our galaxy. The white dwarf is thought to have turned into a ‘thermonuclear supernovae’ and exploded, kicking US708 and sending it hurtling across space, researchers said.

The discovery of US708 by an international team sheds light on the mysterious double-star systems that give rise to thermonuclear explosions. Thermonuclear, or ‘type Ia’, supernovae have long been used to calculate the distances to faraway galaxies – a measurement which helps to determine how the universe is changing and expanding.

Researchers made the ground-breaking discovery using data gathered by the Pan-STARRS1 telescope on Mount Haleakala on the Hawaiian island of Maui.

Using a range of data gathered over the last 59 years the team were able to determine the full 3-D motion of the star and measure how quickly it is moving across the plane of the sky.

“It brings us a step closer to solving the type Ia puzzle,” Dr Rubina Kotak, from the Astrophysics Centre at Queen’s University Belfast, said.

“Several types of stars have been suspected of causing the explosion of a white dwarf as supernova of type Ia. Until now, none of them could be confirmed. Now we have found a delinquent on the run bearing traces from the crime scene,” European Southern Observatory fellow, Stephan Geier, who led the study, said.