M57: The Ring Nebula
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 Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
