The Hubble Space Telescope has plotted the motions of stars in the giant Omega Centauri cluster so accurately that scientists can predict their motions over the next 10,000 years.
In the resulting videos, presented this week by the Hubble science team, individual stars swarm around the center of the cluster like bees swarming in a hive. Closer analysis could help astronomers figure out how the cluster has evolved.
Mapping the star's motion was a tough job, even for Hubble: The motions of more than 100,000 stars in the cluster, taken over the course of four years, had to be painstakingly tracked using sophisticated high-speed computer programs. The exercise was undertaken to determine whether a middleweight black hole, tens of thousands of times more massive than our sun, was lurking at the center of the cluster.
"The case for such a black hole is weaker than it was before," said Roeland van der Marel, an astronomer at the Baltimore-based Space Telescope Science Institute, "and we also think that if there is a black hole in the center of the cluster, it cannot be as massive as had been previously suggested."
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