Hubble sees starbursts in Virgo
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!
|NGC 4536 [Credit: ESA/Hubble & NASA]|
Star formation leaves a few tell-tale fingerprints, so astronomers can tell where stars have been born. We know that starburst regions are rich in gas. Young stars in these extreme environments often live fast and die young, burning extremely hot and exhausting their gas supplies fairly quickly. These stars also emit huge amounts of intense ultraviolet light, which blasts the electrons off any atoms of hydrogen lurking nearby (a process called ionization), leaving behind often colorful clouds of ionized hydrogen (known in astronomer-speak as HII regions).
Source: NASA/Goddard Space Flight Center [April 14, 2017]