Researchers from the University of Nottingham calculate some 36 intelligent communicating civilizations active in our galaxy , with a new approach published in The Astrophysical Journal . Using the assumption that intelligent life forms on other planets in a similar way as it does on Earth , these scientists have estimated the number of technological civilizations within the Milky Way .
Nottingham University Professor of Astrophysics Christopher Conselice, who led the research, explains in a statement: “There should be at least a few dozen active civilizations in our galaxy under the assumption that it takes 5 billion years for it to form intelligent life on other planets, such as on Earth. ” Conselice also explains that “the idea is to look at evolution, but on a cosmic scale. We call this calculation the Copernicus Astrobiological Limit .”
First author Tom Westby explains: “The classical method of estimating the number of intelligent civilizations is based on guessing about life-related values, so opinions on these matters vary substantially. Our new study simplifies these assumptions using new data, giving us a solid basis for estimating the number of civilizations in our galaxy. ” Copernicus’ two astrobiological limits are that intelligent life forms in less than 5 billion years, or after about 5 billion years, similar to that of Earth , where a communicating civilization formed after 4.5 billion years. “On the solid criterion, according to which a metal content equal to that of the Sun is needed (the Sun is relatively rich in metals), we calculate that there should be around 36 active civilizations in our Galaxy,” says Westby.
Research shows that the number of civilizations largely depends on how long they actively send signals of their existence into space, such as radio broadcasts from satellites, television, etc. If other technological civilizations last as long as ours, which is currently 100 years old, then there will be around 36 ongoing intelligent technical civilizations across our galaxy.