Relatively few galaxies possess the
sweeping, luminous spiral arms or brightly glowing center of our home galaxy
the Milky Way. In fact, most galaxies look like small, amorphous clouds of
vapor. One of these galaxies is DDO 82, captured by the Hubble Space Telescope.
Though tiny compared to the Milky Way, such dwarf galaxies may contain between
a few million and a few billion stars.
DDO 82, also known by the designation
UGC 5692, is not without a hint of structure, however. Astronomers classify it
as an "Sm galaxy," or Magellanic spiral galaxy, named after the Large
Magellanic Cloud, a dwarf galaxy that orbits the Milky Way. That galaxy, like
DDO 82, is said to have one spiral arm.
DDO 82 can be found in the constellation
of Ursa Major (the Great Bear) approximately 13 million light-years away. The
object is considered part of the M81 Group of around three dozen galaxies. DDO
82 gets its name from its entry number in the David Dunlap Observatory
Catalogue. Canadian astronomer Sidney van den Bergh originally compiled this
list of dwarf galaxies in 1959.
The image is made up of exposures taken
in visible and infrared light by Hubble’s Advanced Camera for Surveys.
Image Credit: ESA/NASA
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