A starburst is an astronomical event that results in the formation of a cluster or groups of stars. It is usually triggered by the collision of two galaxies, which can lead to a rapid increase in the rate of star formation. The resulting starburst can last for up to a few hundred million years and can create some of the most massive and luminous stars in the Universe.
Starbursts are thought to play an important role in the evolution of galaxies, as they can trigger both positive (e.g., through increased star formation) and negative (e.g., through supernova explosions) feedback on their host galaxies. Additionally, starbursts can be used as probes of galaxy evolution, as they can provide insights into how galaxies interact and evolve over time.
Some of the best-known examples of starbursts are found in so-called ultraluminous infrared galaxies (ULIRGs), which are extremely bright at infrared wavelengths due to their intense star formation activity. ULIRGs are often associated with major mergers between gas-rich spiral galaxies, and it is thought that this interaction triggers the burst of star formation. Other examples include dwarf irregular galaxies, which often experience bursts of star formation due to their small size and shallow potential wells, allowing gas to more easily collapse into new stars.
While moststarbursts occur in relatively rare events, there are a few notable exceptions. One example is our own Milky Way galaxy, which is currently undergoing a period of enhanced star formation known as its “baby boom”. This period began around 10-12 million years ago and will likely continue for another few million years; during this time, our galaxy is expected to form several hundred thousand new stars!