NASA announced new discoveries in the search for life on other planets. After discoveries made by the Kepler telescope, scientists have announced the existence of three planets that are among the best candidates for supporting life, and one of them may be the most Earth-like alien planet identified to date.
The Kepler telescope, part of a satellite launched to continue our analysis of far away star systems in our quest to answer the question of “Are we alone?” Currently the satellite is tracking over 150,000 stars in an attempt to identify potential life-sustaining planets. Today’s announcement centers on the star Kepler-62 (which appears comparable to the Earth’s sun) and two of its five orbiting planets.
The two most interesting of the star’s planets are Kepler-62e and Kepler-62f. They are the furthest of Kepler-62’s planets. Kepler-62e and Kepler-62f “look very good as possibilities for looking for life,” said Kepler science investigator Bill Borucki, of NASA’s Ames Research Center in California. According to estimates, Kepler-62f is 1.4 times the size of the Earth, while Kepler-62e is roughly 1.6 times larger. This makes the pair the smallest planets ever identified in the “habitable zone” in a solar system. This is the zone in which planets are the right distance from their star to hold the most potential for life-sustaining liquid water. These two planets are described in a study released today in the journal Science.
The third planet, which was not part of the study, is Kepler-69c. It is roughly 1.7 times larger than the Earth and is the smallest planet ever identified within the habitable zone of a sun-like star. Kepler-69c appears to be the closest an alien world has come to being Earth-like. With every new discovery, “we’re moving very rapidly toward finding an Earth analogue around a star like the sun,” said Borucki. Kepler-69c and its solar system are discussed in a study published in The Astrophysical Journal.
“With all of these discoveries we’re finding, Earth is looking less and less like a special place and more like there’s Earth-like things everywhere,” according to Thomas Barclay, Kepler scientist at the Bay Area Environmental Research Institute in Sonoma, California. But before we start looking into travel plans, it may be a while before these planets are on the tourist route. Kepler-62 is 1,200 light-years away from the Earth in the constellation Lyra and Kepler-69 is part of the constellation Cygnus and is 2,700 light-years away. A light-year is the distance light will travel in a vacuum in a year—roughly 6 trillion miles.
The Kepler telescope, which was launched in March 2009 and carried a price tag of $600 million, was designed to search out earth-sized planets that fall within their star’s habitable zone. It uses a technology that identifies small drops in brightness as the planet crosses the star’s face according to the satellite’s instrumentation. To date Kepler has identified 2,700 planets it deems meets the criteria. Of those 2,700, 122 of them have been confirmed, although Kepler scientists believe that up to 90 percent of them will eventually be confirmed.
While the Kepler process can identify potential life-sustaining planets, it cannot provide any information regarding the atmosphere on these planets or make any judgment on whether or not life may be present. According to Barclay, “future NASA missions are going to focus on more nearby stars that we can look at in much more detail.” This discovery is an amazing announcement in our ongoing quest to understand our place in the heavens, but many questions still remain. But Borucki assures us that “this is one of the early steps, but there’s no mistake — we are on our way to explore the galaxy, to learn about life in the galaxy.”