Every large galaxy has a supermassive black hole at its core. Usually, the mass of such a hole is of about 1 million suns. Now, a new study claims that these black holes, which act like vacuum cleaners, do more than destroy everything near them. They are able to grow so much that they no longer allow the galaxy to create new stars. Basically, it makes them sterile. Experts have known for a long time that young galaxies are full of new and bright stars. However, as time passes, stars are no longer being formed. This new study, which the journal Nature published, claims that supermassive black holes are to blame for this phenomenon.
Cold gas is what forms new stars. So, when a galaxy no longer has cold gas, stars cannot be born. There is an explanation for this. A supermassive black hole attracts the gas and produces high-energy jets. This energy is what expels the cold gas out of that galaxy, making it unable to give birth to other stars.
The formation of stars
This new study, which Ignacio Martín-Navarro led, proves that supermassive black holes are indeed the cause for sterile galaxies. In order to reach this conclusion, the team used data from the Hobby-Eberly Telescope Massive Galaxy Survey. This is how they managed to separate and measure the wavelengths of light coming from distant galaxies. After this, they created a history of a galaxy’s star formation. Upon comparing this with the history of black holes, they realized that their mass was what made galaxies sterile.
Navarro explained that galaxies that have bigger black holes become unable to create new stars sooner than other galaxies. And while this conclusion is extremely interesting, the experts agree that they still need to do more research. They are still not sure about the entire process that makes galaxies sterile.
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