On May 10th, NASA announced that their Kepler mission verified 1,284 new exoplanets – the single largest finding of planets to date.
According to NASA’s press release, prior to the launch of NASA’s Kepler space observatory in March of 2009, “[scientists] did not know whether exoplanets were rare or common in the galaxy. Thanks to Kepler and the research community, we now know there could be more planets than stars,” said Paul Hertz, Astrophysics Division director at NASA Headquarters.
Kepler’s job is to study a portion of the Milky Way to search for planets, staring at over 100,000 stars. Kepler is able to discover these planets by detecting decreases in brightness that occur when planets pass in front of, or transit, their stars. A great example of this is when Mercury passed across the Sun earlier this week.
“In the newly-validated batch of planets, nearly 550 could be rocky planets like Earth, based on their size. Nine of these orbit in their sun’s habitable zone, which is the distance from a star where orbiting planets can have surface temperatures that allow liquid water to pool. With the addition of these nine, 21 exoplanets now are known to be members of this exclusive group,” according to NASA’s press release.