What Causes Galaxies To Create “Bursts” Of New Stars?

There is a special type of galaxy out in the great yonder dubbed the “starburst galaxy.” The reason for such a name? It has the ability to produce stars at a rate that is 1,000 times faster than any grouping of stars or gasses found within our Milky Way.

After researching the closest starburst galaxy, known as the Sculptor Galaxy, or formally NGC 253, scientists have a few additional clues as to just how these entities are able to build new stars at such an astonishing rate.

Courtesy of the Atacama Large Millimeter/submillimeter Array (ALMA), located in northern Chile, we have photographs depicting the inside of the Sculptor Galaxy, where stellar nurseries are going about their business producing new stars.

While we may all remember that stars are formed from dense clusters of gas and dust, scientists were unable to determine the relationship between the intensity of star formation and the surrounding elements. However, massive amounts of carbon monoxide were found within the area of NGC 253.

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Carbon Monoxide in the Sculptor Galaxy

Scientists have used the data to determine that areas where the density and heat are ten times greater than those found in the Milky Way are the places where a greatly accelerated rate of star formation is most likely to occur.

Yet, a bubbling cauldron of gas is not the only thing needed to create a starburst galaxy. Astronomers often consider this type of galaxy to be a phase that can be activated when one galaxy comes near or even collides with another. This can cause the gas within one or both of the colliding galaxies to spiral towards the center, become more concentrated, and as a result, burst forth as new stars.

Adam Leroy, professor at Ohio State University and an active user of the Atacama Large Millimeter Array, states that not only do these galaxies contain more gas and dust, but that the types of gas itself are more effective in producing new stars.

His team is still going through the data, shifting from region to region inside the galaxy, with the hope of understanding how different gases at different densities can create new stars at a vastly accelerated level.