WASHINGTON — The discovery four years ago of a rocky, not-too-distant planet that seemed a prime candidate for alien life was a thrilling development in the search for other Earths — proof, it seemed, that our planet was not the only one with just the right mix of life-sustaining conditions.
But two scientists at Penn State University say they have debunked the possibility of a “Goldilocks” planet once believed to revolve around Gliese 581, a faint dwarf star that is 20 light-years from Earth.
Using a new technique they are developing to confirm the existence of small, hard-to-detect planets, the researchers say they have determined that physical changes within the star itself created the illusion of an orbiting Goldilocks planet and a second one that also does not exist.
Three other planets do exist, they said, in the Gliese 581 planetary system, but none within the star’s “habitable zone” — an area just the right distance from the star to allow the presence of liquid water.