A star three times bigger than the sun has been seen fleeing our galaxy
at over 1.5 million mph, according to astronomers at the
Harvard-Smithsonian Center for Astrophysics.
The gravitational pull of a black hole thought to exist there is
likely responsible for the extreme velocity of the star, swinging it
around the center of the Milky Way. A companion star may once have
traveled with the speeding star and contributed to its velocity before
being trapped by the black hole.
The first-of-its-kind finding not only confirms an earlier theory about
the existence of such speeding stars, but also reinforces the notion
that the Milky Way spins around a black hole, said Warren Brown, a
postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics
and a member of the team that discovered the star.
"It’s a hypothesis on our part, but there’s no other good way of
explaining a star moving this fast," said Brown. "The only way to get
velocity that high on a star is you have to interact with something
more extreme, like a black hole."
The star is currently 180,000 light years from Earth. Based on its
trajectory, the astronomers believe it will exit the Milky Way and
scream through miles of empty space until it burns out.
"The space between galaxies is extremely empty," said Brown. "It
will have a nice view of the Milky Way for a while. At some point, the
night sky from that star would look like a couple big galaxies. But
everything else would be pure black."