US astronomers have discovered a star cluster that broke away from a distant galaxy and is now speeding towards Earth at more than two million miles per hour.
Luckily, researchers at the Harvard-Smithsonian Center for Astrophysics (CfA) say that the cluster ejected from galaxy Messier 87 (M87) is likely to miss us and instead “drift through the void between the galaxies for all time”.
It was by chance that the scientists found the hypervelocity globular cluster HVGC-1, withe the team using the Hectospec instrument on the MMT Telescope in Arizona to examine hundreds of star clusters in detail. A computer automatically analysed the data, with oddities examined by hand, and while the rest of the anomalies were glitches, the high velocity of HVGC-1 was real.
Nelson Caldwell of the CfA, and lead author on the study due to be published in The Astrophysical Journal Letters, said:
“Astronomers have found runaway stars before, but this is the first time we’ve found a runaway star cluster”
Astronomers are not certain how HVGC-1 was ejected from the M87 galaxy, but in one scenario the galaxy has two black holes at the centre, which could have “acted like a slingshot”, firing the cluster away at a very high speed.
