Two "goldilocks" planets that were suspected to hold life have been proven false.
Researchers found signals that were believed to be coming from two planets orbiting a star were actually coming from inside the star itself. This finding disputed the existence of these "Goldilocks planets," which could potentially support water or even life, Penn State reported.
The study was published in the July 3 edition of Science Express.
"This result is exciting because it explains, for the first time, all the previous and somewhat conflicting observations of the intriguing dwarf star Gliese 581, a faint star with less mass than our Sun that is just 20 light years from Earth," said lead author Paul Robertson, a postdoctoral fellow at Penn State who is affiliated with Penn State's Center for Exoplanets and Habitable Worlds.
The findings suggest there are three planets orbiting this distant star. None of these three planets are believed to orbiting within the hospitable zone of their host star.
"We also have proven that some of the other controversial signals are not coming from two additional proposed Goldilocks planets in the star's habitable zone, but instead are coming from activity within the star itself," said Suvrath Mahadevan, an assistant professor of astronomy and astrophysics at Penn State and a coauthor of the research paper.
Older stars in the Libra constellations, such as Gliese 581, have been a target in the search for extraterrestrial life because they are less active and more accessible for Doppler investigations.
"The new result from our research highlights a source of astrophysical noise even with old M dwarfs because the harmonics of the star's rotation can be in the same range as that of its habitable zone, raising the risk of false detections of nonexistent planets," Mahadevan said. "Higher-precision analysis for discovering Earth-like planets using spectrographs will be increasingly more necessary as next-generation spectrographs with the higher Doppler precision needed for detecting important subtle signatures come on line this decade -- like the Habitable Zone Planet Finder (HPF) that our team now is developing at Penn State."
