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Apr 19, 2015
Ring Galaxy AM 0644-741 from Hubble
Image Credit & Copyright: Astronomy Picture of the Day -- http://apod.nasa.gov/apod/astropix.html
Courtesy of http://apod.nasa.gov/apod/astropix.html
Ring Galaxy AM 0644-741 from Hubble
Image Credit & Copyright: Astronomy Picture of the Day -- http://apod.nasa.gov/apod/astropix.html
Courtesy of http://apod.nasa.gov/apod/astropix.html
How could a galaxy become shaped like a ring? The rim of the blue galaxy
pictured on the right is an immense ring-like structure 150,000
light years in diameter composed of newly formed, extremely bright,
massive stars.
That galaxy, AM 0644-741, is known as a
ring galaxy and was caused by an
immense galaxy collision.
When galaxies collide,
they pass through each other -- their individual stars
rarely come into contact.
The ring-like shape is the result of the
gravitational disruption
caused by an entire
small intruder galaxy passing through a large one.
When this happens, interstellar gas and
dust become condensed, causing a
wave of star formation
to move out from the impact point like a
ripple across the surface of a pond.
The intruder galaxy is just outside of the frame taken by the
Hubble Space Telescope.
This featured image was taken to
commemorate the anniversary of
Hubble's launch
in 1990.
Ring galaxy AM 0644-741 lies about 300 million light years away.
