NASA’s Kepler Space Telescope has spotted more than 4,000 candidate planets for follow-up study. Scientists have just verified the 1,000th planet.
Eight more candidate planets were verified as actual planets recently. But, scientists still have a lot of work in front of them. While they verified these eight, the Kepler team sent them another 554 candidate planets. 3 of these are orbiting their host star in the habitable zone. The area where liquid water may exist. Two of these are probably made of rock.
The Kepler team monitors more than 150,000 stars in their hunt for exoplanets.
John Grunsfeld, associate administrator of NASA’s Science Mission Directorate, says each new data dump from the Kepler mission “takes us another step closer to answering the question of whether we are alone in the Universe.”
Here’s a closer look at the two exoplanets scientists believe are made of rock.
Kepler-438b and Kepler-442b are similar in size to our home. 438b is located 475 light-years away and is 12% bigger than Earth. It orbits its host star once every 35.2 days.
442b lies 1,100 light-years away and is a bit bigger. It’s 33% bigger than Earth and orbits its star once every 112 days.
The two planets orbits’ are closer to their host star. Each planet’s star is smaller and cooler than our sun. So, the habitable zone is closer to the star.
“Kepler collected data for four years — long enough that we can now tease out the Earth-size candidates in one Earth-year orbits”, said Fergal Mullally, SETI Institute Kepler scientist at Ames who led the analysis of the potential Earth-like planets.
“We’re closer than we’ve ever been to finding Earth twins around other sun-like stars. These are the planets we’re looking for.”
Next up for scientists? Figuring out how common rocky planets are around a star’s habitable zone. Oh, and parsing through the new exoplanet candidates. More sophisticated software will help scientists find small, Earth-size planets.