starburst tagged posts

Although galaxy formation and evolution are still far from being fully understood, the conditions we see within certain galaxies — such as so-called starburst galaxies — can tell us a lot about how they have evolved over time. Starburst galaxies contain a region (or many regions) where stars are forming at such a breakneck rate that the galaxy is eating up its gas supply faster than it can be replenished! Credit: ESA/Hubble & NASA

Although galaxy formation and evolution are still far from being fully understood, the conditions we see within certain galaxies – such as starburst galaxies – can tell us a lot about how they have evolved over time...

This megamaser galaxy is named IRAS 16399-0937 and is located over 370 million light-years from Earth. This NASA/ESA Hubble Space Telescope image belies the galaxy’s energetic nature, instead painting it as a beautiful and serene cosmic rosebud. The image comprises observations captured across various wavelengths by two of Hubble’s instruments: the Advanced Camera for Surveys (ACS), and the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). Credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt

Megamasers are intensely bright, around 100 million times brighter than the masers found in galaxies like the Milky Way. The entire galaxy essentially acts as an astronomical laser that beams out microwave emission rather than visible light (hence the ‘m’ replacing the ‘l’)...

This is a dwarf galaxy with a starburst. Credit: UC Riverside

Astronomers use computer simulations based on theoretical models to explain massive star formation observed in dwarf galaxies. One of the main predictions of the current model of the creation of structures in the universe, known at the Lambda Cold Dark Mattermodel, is that galaxies are embedded in very extended and massive halos of dark matter surrounded by many thousands of smaller sub-halos also made from dark matter.

Around large galaxies, eg Milky Way, these dark matter sub-halos are large enough to host enough gas and dust to form small galaxies on their own, and some of these galactic companions, known as satellite galaxies, can be observed...