The figure includes 10 that are "rocky" like Earth and which exist in their solar system's "Goldilocks zone", neither too close to their star, and therefore too hot, nor too far away and too cold for liquid water to exist.
Speaking about the discovery Thomas Zurbuchen, associate administrator of the agency's Science Mission Directorate in Washington said: "Answering the question "are we alone" is a top science priority and finding so many planets like these for the first time in the habitable zone is a remarkable step forward toward that goal".
The planet candidates, announced this afternoon by the United States space agency, are in the final catalogue from Kepler's survey of the patch of sky in our galaxy known as the Cygnus constellation. Of the verified planets, there are roughly 50 that are close to Earth in size and orbit their stars in the habitable zone.
Scientists at NASA's Ames Research Centre in California on Monday revealed the "most reliable" catalogue yet of potential planets in the galaxy, bringing the total to 4034. If confirmed, they would be added to a small but growing list of Earth-sized planets that occupy our corner of the Milky Way galaxy, supporting the idea that rocky worlds are more common than we once thought.
NASA said the latest catalog is the most complete and detailed survey of potential exoplanets yet compiled.
The latest batch of over 200 planets can be separated into two distinct groups - Earth-size planets and gaseous planets smaller than Neptune. That happens during a so-called "transit" - when a planet passes in front of its star.
No longer out of bounds: Trump allies question Mueller probe
The White House downplayed Ruddy's comments. "This clown over here, Mueller, thinks he can tell you what to do". The White House dismissed Ruddy's comments - but not by saying Mueller is safe.
Tougher Trump line toward Cuba delights hardliners on island
White House officials also said it's the category most ripe for abuse, with Americans using it to skirt the tourism ban. But at the same time, Trump often criticizes regulations on the business community as "burdensome" and "job-killing".
American soldiers wounded, not killed in incident at Afghan base
A statement on the Resolute Support Twitter feed Saturday says the seven were wounded when an Afghan army soldier opened fire . The Afghan military statement said that the rogue soldier had also been killed .
Fans of the Drake Equation can rejoice, because NASA just announced that the Kepler spacecraft, which has been scanning the stars to find more exoplanets, has discovered 1,284 new planets, which NASA calls "the single largest finding of planets to date".
Of the 10 newly discovered Earth-size planets, one is the closest to Earth in size and the distance to its host star.
"Understanding their frequency in the galaxy will help inform the design of future Nasa missions to directly image another Earth".
An exoplanet is a planet that exists outside of our own solar system.
This is the eighth release of the Kepler candidate catalog, gathered by reprocessing the entire set of data from Kepler's observations during the first four years of its primary mission.
Scientists were even able to estimate the size and density of the planets.
Some exoplanets closely resemble Earth and are a few of the best places to look for alien life. In the mid-2020s, we have our sights on taking a picture of small planets like Earth with our Wide-Field Infrared Survey Telescope (WFIRST). Researchers are now using the Hubble Space Telescope to determine if these planets had atmosphere.