Relatively few galaxies are endowed with the sweeping, luminous spiral arms or brightly glowing center of our own Milky Way galaxy.
Rather, most of the Universe’s galaxies look like small, amorphous clouds of vapor. One such galaxy is DDO 82, captured in the picture below as an image from the NASA/ESA Hubble Space Telescope.
Though tiny compared to the Milky Way, such dwarf galaxies still contain between a few million and a few billion stars.
However, DDO 82 – also known by the designation UGC 5692 – is not without a hint of structure. Indeed, 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 believe to have one spiral arm.
In the case of DDO 82, gravitational interactions over its history seem to have discombobulated it so that this structure is not as obvious as in the Large Magellanic Cloud. Thus, astronomers also refer to DDO 82 and others of a similar unshapely nature as dwarf irregular galaxies.
DDO 82 is located in the constellation of Ursa Major (the Great Bear) approximately 13 million light-years away. The object is categorized as belonging to the M81 Group, comprising approximately three dozen galaxies.
