KISSIMMEE, Fla. -- Densely packed clusters of stars on the fringes of our Milky Way galaxy may be home to intelligent life. That's the word from an astrophysicist who's new to probing extraterrestrial territory.
The approximately 150 globular clusters in our galaxy are old and stable, a plus for any civilization, said Rosanne Di Stefano of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts. In addition, so many stars are clumped together it would be easy to hop from one place to another, keeping an advanced society going.
The first step, she said, is to locate more planets in these clusters. So far, only one has been found. The sweet spot would be a habitable zone around a star where life could flourish, yet dense enough to enhance travel among inhabitants.
Di Stefano presented her theory Wednesday at the American Astronomical Society's annual meeting in Kissimmee, Florida. Her paper stood out among the hundreds of research papers; an AAS official called the results "provocative."
A global cluster can hold a million stars in a compact ball an average 100 light-years across. This overcrowding can result in stars elbowing out other stars' planetary systems. Di Stefano said smaller solar systems would be more apt to last longer; the planets would orbit closer to their home star and therefore be less of a target for encroaching neighbors.
Stars in these clusters are so close, communication and travel would be relatively easy for these any space-farers out there.
"We call it the 'globular cluster opportunity,'" Di Stefano explained in a statement. "Sending a broadcast between the stars wouldn't take any longer than a letter from the U.S. to Europe in the 18th century."
Di Stefano stressed at a news conference that her premise is scientific conjecture. "I want to make this clear — we don't know," she told reporters. Nevertheless, the possibility of a long-lived civilization is fascinating, she noted, so what better place to look than these 10 billion-to-12 billion-year-old global clusters.
"Global clusters are good targets to spend your time on in search of extraterrestrial intelligence," she urged.