irregular galaxy


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irregular galaxy
Messier 82

irregular galaxy

n.
A galaxy that does not have the clearly defined shape and structure of an elliptical, lenticular, or spiral galaxy. Irregular galaxies typically contain large amounts of gas and dust, and their stellar populations are relatively young.
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M82, also called the Cigar Galaxy, is a spiral galaxy that was first considered an irregular galaxy.
The galaxies M81 and M82 in Ursa Major are an interesting pair, M81 being a traditional spiral galaxy, and M82 an active irregular galaxy.
The radio supernova was discovered on April 8 in M82, a small irregular galaxy located nearly 12 million light years from Earth in the M81 galaxy group, by the Very Large Array, a New Mexico facility operated by the National Radio Astronomy Observatory (NRAO).
Neff suggests that gravitational pull from another galaxy that passed nearby, perhaps the irregular galaxy M82, could have helped form the ring-shaped feature.
Originally classified as an irregular galaxy, M82 images taken in 2005 in the near infrared revealed two symmetric spiral arms aligned edge-on to our line of sight.
Some identify NGC 3447B as a former spiral galaxy, while others categorize it as being an irregular galaxy.
com/hubble-space-telescope-spies-distant-collision-between-two-gas-rich-spiral-galaxies-2473696) a photograph of IRAS 14348-1447, a gas-rich irregular galaxy that astronomers believe was created when two spiral galaxies ventured too close, each getting caught in the other's gravitational pull - an act of mutual destruction that ended in the galaxies' deaths, and the birth of a new one.
Using averted vision I can spot the irregular galaxy NGC 4068 in the same field of view, 23' west-southwest of its neighbor, with two faint yet distracting stars to its west.
The mass, size and rotational velocity of NGC 4861 - as it's formally known - resemble those of a spiral galaxy, while its diffuse appearance makes it look like a dwarf irregular galaxy.
Starburst "There are many indications that NCC 1569, a small 11th-magnitude irregular galaxy in Camelopardalis, underwent a tremendously violent burst of star formation millions of years ago.
Another instance of the gravitational interactions between massive galaxies can be seen in an image of the irregular galaxy IC 3583 released earlier this month.