M57: The Ring Nebula
Credit: H. Bond (STSci), R. Ciardullo (PSU), WFPC2,
HST, NASA
Explanation: It looked like a ring on the sky. Hundreds of years ago
astronomers noticed a nebula with a most unusual shape. Now known as M57 or NGC
6720, the gas cloud became popularly known as the
Ring Nebula. It is
now know to be a
planetary
nebula, a gas cloud emitted at the end of a Sun-like star's existence. As
one of the brightest
planetary
nebula on the sky, the
Ring
Nebula can be seen with a small telescope in the constellation of
Lyra. The
Ring Nebula lies about 4000
light years away, and is roughly 500 times the diameter of our
Solar System. In
this recent picture
by the
Hubble Space Telescope,
dust filaments and
globules
are visible far from the central star. This helps indicate that the
Ring
Nebula is not spherical, but cylindrical. Perhaps the
Ring Nebula would
appear
differently if viewed
sideways.
Authors & editors: Robert Nemiroff (MTU) & Jerry
Bonnell (USRA)
NASA Technical Rep.:
Jay Norris. Specific rights apply.
A service
of: LHEA at NASA/ GSFC
&: Michigan Tech. U.
