Centaurus A: Young Blue Star Stream
Almost lost in this cosmic jumble of stars, gas and dust is a faint but
definite blue arc -- a
stream of young stars whose formation was
probably triggered as a small dwarf galaxy was
torn apart
approaching the giant elliptical galaxy
Centaurus A.
The 2,000 light-year long arc is revealed in the upper right corner of
this
processed color
digital image, while the dense central region
of Centaurus A is near the bottom.
Star clusters that make up the blue arc are likely strung out along the
incoming trajectory of the small galaxy and are estimated to be only
200-400 million years old.
The remarkable result
suggests that astronomers have identified
a spectacular example of a kind of galactic cannibalism in progress,
a process which is believed to contribute to the formation and
evolution
of large galaxies, including our own
Milky Way.
Over time, stars and star clusters in this stream should
eventually disperse and merge
with tumultuous Centaurus A.
The image data was recorded with the four meter
Blanco
telescope at Cerro Tololo Inter-American Observatory.