Forty volunteer astronomers have announced the discovery of 42 new alien planets, approximately 15 of which may be habitable worlds.
This marks the second exoplanet discovery by the Planet Hunters project, a crowd-sourced project overseen by Zooniverse. These amateur astronomers pour over NASA’s freely available data and amass evidence of new exoplanets. One of the planets among the team’s latest discovery, PH2 b, is a massive planet that has an atmospheric temperature between 30 and minus 88 degrees Celsius, or 86 and minus 126 degrees Fahrenheit. Researchers at the W.M. Keck Observatory in Hawaii have confirmed PH2 b with 99.9 percent confidence.
PH2 b is a Jupiter-size planet that orbits within the “Goldilocks zone” around a star. In order for a planet to support life, the atmospheric conditions need to permit water to liquify on the surface; temperatures can be neither too hot nor too cold. With 15 planets orbiting within the habitable zone of their parent star, this particular solar system may boast many more life-supporting worlds than our own.
While PH2 b is considered much too large to support life, one of its moons may a livable world. If a PH2 b moon were habitable, researchers say it would probably have a greenhouse atmosphere, liquid water on its surface, and a rocky core.
Postdoctoral researcher at Yale University, Ji Wang, is the lead author of a paper on the discoveries that is available on the pre-publishing website Arxiv. Wang likened this possible moon world to the one in the movie Avatar. With both moons orbiting giant planets in habitable zones, the fictional moon of Avatar and this would-be moon world orbiting PH2 b might prove surprisingly similar upon further investigation.
In order to find new exoplanets, the amateur astronomers of the Planet Hunters project sort through data from NASA’s Kepler Space Telescope. The team used one of the two main methods of new planet discovery; by observing a parent star and watching for any dimness. If the star’s brightness from Earth decreases, this signals a planet passing in front of it, much like a solar eclipse may be viewed from Earth. The alternative method of finding new planets involves looking for wobbles in a star’s gravity, which would indicate a planet is orbiting around it.
After the team finds the best candidates, professionals investigate further to confirm the planets’ existence. So far the Planet Hunters project has found 48 candidate planets. In October 2011, PH1 was the first planet confirmed.
While Planet Hunters team members are from Oxford, Yale and other higher education institutions, no special knowledge or training is required to participate in the process; anyone can join their efforts and help discover a new planet.
The Planet Hunters team awaits confirmation of their discoveries by professional astronomers.