Stellar Motions In Outer Halo Reveal Evidence Of Milky Way
Evolution April Flowers for redOrbit.com – Your Universe Online
Astronomers using NASA’s Hubble Space Telescope to peer deep
into the vast stellar halo that envelopes our galaxy have
uncovered tantalizing evidence for the possible existence of a
shell of stars that are a relic of cannibalism by our Milky Way.
For the first time ever, Hubble was used to gain precise
measurements of the sideways motion of a small sample of stars
located far from the galaxy’s center. The unusual lateral motion
of these stars is circumstantial evidence that they may be the
remnants of a shredded galaxy that was gravitationally
devastated by the Milky Way billions of years ago. The presence
of these stars supports the theory that the Milky Way grew, at
least in part, through the accretion of smaller galaxies. The
findings of this study will appear in an upcoming issue of the
Astrophysical Journal. “Hubble’s unique capabilities are
allowing astronomers to uncover clues to t