Nikolai Kardashev, a Russian astrophysicist, was one of the founders of the search for extraterrestrial intelligence (SETI). In 1964, Kardashev published a paper proposing a way to categorize a planet's energy use, a system that has come to be known as the Kardashev Scale.
In 1964, when Kardashev published his paper, SETI was still a very young field. But now, a growing number of researchers are actively looking for technosignatures that indicate intelligent life elsewhere in the galaxy.
Search for Extraterrestrial Intelligence
Pinchen Fan is one of those researchers. An astrophysicist at Penn State University, Fan searches for radio and laser technosignatures using ground-based telescopes.
“A technologically advanced civilization will leave behind evidence of their existence,” she says. “So we're trying to find evidence of their technological activity. They're gonna leave something behind.”
