Old, dense, and isolated star clusters can be the perfect place to find intelligent life beyond Earth, say scientists who have presented a study on how so-called “globular clusters” can be the cradle of life for advanced civilizations.
“If they contain planets, globular clusters provide ideal conditions for advanced civilizations that can survive for a long time,” astronomer Rosanna Di Stefano of the Harvard-Smithsonian Astrophysics Center wrote in a document that will be presented at the meeting of the American community in Orlando, the state Florida, this week.
“If there are indeed planets found there and if our guesses are correct, then the search for intelligent life must be done just in globular clusters,” Di Stefano wrote.
Globular clusters typically contain about 1 million stars in a region that is 100 light-years across. The Milky Way Galaxy contains about 150 globular clusters located in the outermost areas of the galaxy. So far, only one planet has been discovered in a globular cluster, but Di Stefano does not take into account the views of critics who believe that the old metal-poor stars are stingy on the planets.
"Exoplanets were found around stars that have only a tenth of the heavy elements present in the sun," said Di Stefano.
"It’s premature to say that there are no planets in globular clusters," said Alleghe Ray from the Tata Institute for Basic Research in Mumbai.
If habitable planets could form in globular clusters and survive for billions of years, then life would have enough time to evolve into a more complex life and even develop potential intelligence.
It would be much easier for the hypothetical civilizations inhabiting globular clusters to communicate with each other, since the stars in such clusters are much closer than in the Milky Way.
"The nearest star in the globular cluster can be about 20 times closer, at a distance of only 1 trillion miles. This would make interstellar communication much more accessible," added Di Stefano.
