NASA has announced the discovery of 1,284 exoplanets orbiting distant stars outside our solar system. It is the highest number of exoplanets announced at one time. The US space agency said during a press conference that nine of the newly discovered planets are in the Goldilocks zone of stars. Planets in the Goldilocks zone have the right temperatures to host liquid water on their surface, potentially supporting life.

NASA Discovers 1,284 Exoplanets; 9 In Habitable Zone

NASA scientists intrigued by some habitable planets

Using data from the Kepler space telescope, NASA said 1,284 were confirmed planets among 4,300 potential candidates identified by a new statistical analysis. The latest announcement more than doubles the number of confirmed planets from Kepler. Paul Hertz, Astrophysics Division director at NASA, said most stars in our galaxy host planetary systems.

Ellen Stofan, chief scientist at NASA, said the discovery gives us hope that we may not be alone in the universe. Kepler mission scientist Natalie Batalha told reporters that she was “intrigued” by the habitable planets including the Kepler-1638b and Kepler-1229b that have sizes comparable to Earth. They are about the right distance from their host stars to have the right temperature necessary for life as we know it.

Researchers use a new statistical analysis

The mega-discovery can be partially attributed to a new statistical method of validating exoplanet candidates. Previously, scientists used a time-consuming process which involved using ground-based telescopes or radial velocity to determine mass in order to confirm a candidate as a planet. It would be followed up by a variety of other observations. Candidates can sometimes give false positives or create imposter scenarios.

Now they use statistical analysis to assign each candidate found by Kepler a planet-hood probability percentage. It gives NASA a way to quantify the probability that a candidate is indeed a planet. It doesn’t require follow-up observations, saving a lot of time and resources. Since its launch in 2009, Kepler has been monitoring more than 100,000 stars to find exoplanets. The telescope spots potential candidates by looking for slight dimming of stars as planets pass across them.