What Is A Starburst Galaxy?
For space science enthusiasts who may be just starting their space research journeys, three galaxies may be the only galaxies imagined having existed. Those three would be Elliptical, Irregular, and spiral galaxies. We may have only envisioned three types, but little to our knowledge there is a fourth galaxy in existence. This mysterious galaxy is called a Starburst Galaxy.
Starburst Galaxies are unique. They are unique because they are seen to form stars at an extremely fast rate compared to other galaxies. This rate is 10^3 times faster than average or normal galaxies. Being that Starburst Galaxies have such high levels of star formation, astronomers have concluded the estimated supply of gas and dust that is within the galaxy will not survive past 10^8 years. This means due to intense star formations the events are seen to have begun in a recent time frame, and as a result, such star formations would expire early on.
Starburst galaxies are usually observed in a small region. This region is around a nucleus, but areas with high activity -star formation- can spread throughout the rest of the galaxy. Astronomers have concluded these star formations could have been triggered by tidal interactions. These interactions take place between close passing galaxies or galaxy mergers. As a result, high amounts of gas and dust accumulate within the central region of the galaxy.
Starburst galaxies are known to be some of the brightest galaxies in the Universe. This is caused by massive stars that are formed from accessible gas. These star formations emit high amounts of ultraviolet wavelengths, and those ultraviolet wavelengths are then absorbed by dust that is nearby. Once that occurs it is remitted at infrared wavelengths.
Because of the rapid star formations, the lifespan of Starburst Galaxies is usually quite short. This occurs when supernova explosions and stellar winds possibly sweep gases from the galaxy, which then halts new star formations. This occurrence comes from those massive star formations mentioned earlier.
Starburst Galaxies were once very prevalent early on in the universe unlike now. Most of the Starburst Galaxies – which are about 12 billion light-years apart – are quite alike, and they show that Galaxy interactions were very common in the early Universe.