It hangs out in space some 160,000 light years away. Its neighborhood is the Large Magellanic Cloud. It calls the Tarantula Nebula home. It’s 150 times more massive than our Sun and it shines an astounding three million times brighter. What is it? Try a lone super star…
Utilizing the power of ESO’s Very Large Telescope, a team of international astronomers have been checking out star VFTS 682 in the Large Magellanic Cloud. Using an instrument aptly named FLAMES, they also discovered the star to be very hot, with a surface temperature of about 50 000 degrees Celsius. While most of the initial findings were rather unremarkable, when researchers cleared away the dust clouds they discovered this super star stood alone.
“We were very surprised to find such a massive star on its own, and not in a rich star cluster,” notes Joachim Bestenlehner, the lead author of the new study and a student at Armagh Observatory in Northern Ireland. “Its origin is mysterious.”
Why an enigma? For the most part, stars like VFTS 682 are found in the crowded centers of galactic clusters. They are young, hot and bright – destined to live short and explosive lifetimes. Their high mass makes them a candidate for an even more dramatic end – a long-duration gamma-ray burst, the brightest explosion in the Universe. It could happen to other super stars in the nearby stellar nursery cluster, because it has a sibling.
“The new results show that VFTS 682 is a near identical twin of one of the brightest superstars at the heart of the R 136 star cluster,” adds Paco Najarro, another member of the team from CAB (INTA-CSIC, Spain).
So how did VFTS 682 end up being solitary sun? There is speculation that it could be a “runaway”… ejected from its nest. But such a scenario is unlikely since it is doubtful such a heavy star could be thrown from the cluster by gravitational interactions.
“It seems to be easier to form the biggest and brightest stars in rich star clusters,” adds Jorick Vink, another member of the team. “And although it may be possible, it is harder to understand how these brilliant beacons could form on their own. This makes VFTS 682 a really fascinating object.”
Shine on, you crazy diamond!