The Kepler Space Telescope of the National Aeronautics and Space Administration has once again detected new Earth-like planets that were within the so-called habitable zone, the region around their star that have suitable condition, neither too hot nor too cold, for liquid water to exists on the planet's surface.
In the latest catalog of Kepler's four-year primary mission, NASA added 10 new Earth-like planets. With this latest addition, the number of Earth-sized worlds detected by the space telescope had reached 50. Astronomers have already confirmed the existence of over 30 of those planets.
"With this catalog we're able to extend [our analysis of planets' demographics] out to the longest periods, those periods that are most similar to our Earth," said Susan Thompson, a Kepler research scientist for the SETI Institute in California and lead author of the new catalog, in a press release. "As a result, this survey catalog will be the foundation for directly answering one of astronomy's most compelling questions: How many planets like our Earth are actually in the galaxy?"
To detect new potential planet candidates, the Kepler space telescope uses the so-called "transit method". Astronomers observe stars over a long period of time. When these stars dimmed briefly, it suggests a potential planet is in between the star and the telescope, blocking the telescopes view of the star.
Aside from the 10 new Earth-like planets, the latest catalog from the Kepler mission also includes 209 planet candidates. The addition of the new catalog now puts the number of planet candidates detected by the Kepler space telescope to 4,034. Out of those planet candidates, 2,335 have already been verified as an exoplanet.
In addition to detecting potential planet, data from the Kepler space telescope made two distinct size groupings of small planets. The first group was composed of Earth-like planets, while the second group was composed of mini-Neptunes.