The Whirlpool Galaxy is a classic spiral galaxy.
At only 30 million
light years distant and fully 60 thousand light years across,
M51, also known as
NGC 5194, is one of the brightest and most
picturesque galaxies on the sky.
is a digital combination of a ground-based image from the
0.9-meter telescope at
Kitt Peak National Observatory
and a space-based image from the
Hubble Space Telescope highlighting sharp features normally too red to be seen.
Anyone with a good pair of
binoculars, however, can see this
Whirlpool toward the constellation of the Hunting Dogs
M51 is a
spiral galaxy of type Sc
and is the dominant member of a
whole group of galaxies.
Astronomers speculate that M51's
spiral structure is primarily due to its
gravitational interaction with a
smaller galaxy just off the top of the image.
Credit: N. Scoville
(Caltech), T. Rector
(U. Alaska, NOAO)
et al., Hubble Heritage Team,