Star Kicked Out of Magellan Cloud

No, we’re not talking about a petulant singer and a rock band (though we’re familiar with the type); we’re talking about an unusual astronomic event captured by the European Southern Observatory:

Using ESO’s Very Large Telescope, astronomers [1] have recorded a massive star moving at more than 2.6 million kilometres per hour. Stars are not born with such large velocities. Its position in the sky leads to the suggestion that the star was kicked out from the Large Magellanic Cloud, providing indirect evidence for a massive black hole in the Milky Way’s closest neighbour. These results will soon be published in the Astrophysical Journal Letters [2].

“At such a speed, the star would go around the Earth in less than a minute!”, says Uli Heber, one of the scientists at the Dr. Remeis-Sternwarte (University of Erlangen-Nürnberg, Germany) and the Centre for Astrophysics Research (University of Hertfordshire, UK) who conducted the study.

The hot massive star was discovered in the framework of the Hamburg/ESO sky survey far out in the halo of the Milky Way, towards the Doradus Constellation (“the Swordfish”).

“This is a rather unusual place for such a star: massive stars are ordinarily found in the disc of the Milky Way”, explains Ralf Napiwotzki, another member of the team. “Our data obtained with the UVES instrument on the Very Large Telescope, at Paranal (Chile), confirm the star to be rather young and to have a chemical composition similar to our Sun.”

The data also revealed the high speed of the star, solving the riddle of its present location: the star did not form in the Milky Way halo, but happens to be there while on its interstellar – or intergalactic – travel.

“But when we calculated how long it would take for the star to travel from the centre of our Galaxy to its present location, we found this to be more than three times its age”, says Heber. “Either the star is older than it appears or it was born and accelerated elsewhere”, he adds.

Be sure to check out an artist’s rendering of the star here.

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