Credit: NASA, ESA, and The Hubble Heritage Team (STScI/AURA)
This galaxy appears to be bursting at the seams. The Starburst Galaxy, also called M82 and NGC 3034, shows a bright blue disk surrounded by wispy dark streams of dust and plumes of glowing hydrogen streaking out of its center. M82 is considered by astronomers to be an irregular galaxy because it has no definite shape.
New stars at the heart of the Starburst Galaxy are being born at a rate of 10 times what we see in our own Milky Way. The strong solar winds from all these new stars creates a galactic superwind. This fierce wind pushes gas and dust into more clumps and fuels the birth of more stars. Zoom into the central part of the galaxy and search for bright patches of stars. These starburst clumps are tiny but massive star clusters. Millions of stars are crammed into small spaces. Explore the galaxy and you will notice other pale, white objects sprinkled around the galaxy. They look like fuzzy stars. These are actually great, globular star clusters, about 20 light-years across, made up of up to a million stars. Eventually the rapid star formation will come to a halt after all gas and dust used to make new stars has been used up or spread out too thin. The starburst will eventually disappear.
What do you think causes the red-glowing, expanding cloud of gas and dust from the center of the galaxy? Superwinds blowing from the new, blue stars is part of the answer. The rest of the answer lies in something that is nearby but we cannot see in the image. M82 was recently stirred up by a pass of a nearby large spiral galaxy called M81. These galaxies are locked together by gravity. Eventually they will merge into a gigantic galaxy. While the collision of galaxies sounds dangerous, individual stars will not crash into each other. Stars are very far apart. Gas clouds, however, are very large and will likely collide. The compression of gas and dust will fuel new star formation.
As you zoom in very close to this image from NASA’s Hubble Space Telescope, explore the edges of the galaxy and search for background galaxies. Hundreds of other galaxies far beyond M82 are visible in the image.
M82, also called the Cigar Galaxy because of its elliptical shape, is found in the direction of the constellation of Ursa Major, the Great Bear. The galaxy is located about 12 million light-years from Earth.