A study published this week in the journalNature suggests thatstars known as “red dwarfs” are much more prolific than previously thought, to such an extent that it is likely that the total number of stars in the universe is three times higher than estimated so far.
Red dwarfs are relatively small and faint compared to stars like our Sun, and so astronomers have so far not been able to detect them in galaxies other than the Milky Way or their closest neighbors. Two astronomers from Yale and Princeton Universities (USA) have used powerful instruments from theKeck Observatory in Hawaiito detect thefaint red dwarf trails in eight massive galaxiesrelatively close. They are elliptical galaxies located between 50 and 300 million light years away.
The researchers found that the red dwarfs were much more abundant than expected. Specifically, the team discovered that there are close totwenty times more red dwarfs in elliptical galaxies than in the Milky Way. ? We tend to assume that other galaxies look like our own. But this suggests that other conditions are possible, and hence this discovery could have a major impact on our understanding of galaxy formation and evolution ,? says study co-author Charlie Conroy.
For example, according to Conroygalaxies could contain less dark matterthan previous measurements of their masses indicated. Instead, the abundance of red dwarfs could contribute more mass than previously estimated.
Astronomers say that, in addition to increasing the total number of stars in the universe, the discovery also increases the number of planets orbiting them, which, in turn,raises the number of planets that could support life. “It is possible that there are billions of Earths orbiting these stars,” says Van Dokkum, who recalls that the red dwarfs they have discovered, generally more than 10 billion years old, have had enough time for life to evolve. complex. “It is one of the reasons why science is interested in these types of stars.”
