The Kepler mission team released a survey of 219 potential exoplanets - planets outside of our solar system - that had been detected by the space observatory launched in 2009 to scan the Milky Way galaxy. The new catalog release brings its total catch up to 4,034 potential planets, of which 2,335 are verified exoplanets and almost 50 are near-Earth-size habitable zone candidates. 10 out of these planets are rocky and could potentially have liquid water and support life.
Scientists are also continually updating their scanning models, so it may not be long before the Kepler space telescope finds out how many stars in our galaxy could host an "Earth 2.o".
The Kepler data set is the only set containing a catalog of these near Earth-sized planets with roughly the same orbit, according to Perez. Kepler directly measures the size of planets, and their distance from their stars, meaning there is no way to definitely know whether a planet is habitable.
The planets are only "candidates" at the moment, which means astronomers will need to do more checks to confirm their findings. And it only looked in a tiny part of the galaxy, one-quarter of one percent of a galaxy that holds about 200 billion of stars. Researchers are now using the Hubble Space Telescope to determine if these planets had an atmosphere. Few planets falling between the groupings were also found. These exoplanets were being found by detecting a transit or the minuscule drop in a star's brightness that occurs when a planet crosses the path in front of it.
The last update of planets in Earth's surrounding solar system occured when Pluto was demoted to a dwarf planet in 2006; however, there was talk this year of it being reclassified as a planet.
Kepler's data gives a new chance to assess whether a planet has a solid surface, like Earth, or is made of mostly gas, like Neptune.
"We like to think of this study as classifying planets in the same way that biologists identify new species of animals", said Benjamin Fulton, a doctoral candidate at the University of Hawaii at Manoa, and lead author of the second study.
Mario Perez, a Kepler programme scientist at Nasa, stressed the importance of the space telescope. So far, the space telescope has discovered over 4,000 new exoplanet candidates, over half of which were later confirmed by follow-up observations. The distinction will help scientists home in on potential Earth-like planets and better the odds for finding life.