The number of known planets just doubled

By AG Staff Writer / NASA 11 May 2016
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NASA today announced 1284 new exoplanets – the single largest finding of planets to date, including nine that could be potentially habitable.

NASA’S KEPLER MISSION has verified 1284 new planets orbiting distant stars, doubling the number of confirmed planets.

Of the newly validated planets, 550 could be rocky planets like Earth based on their size, and nine of these orbit in their sun’s ‘habitable zone’ – meaning at a distance that could allow for liquid water to pool. The addition of these nine planets raises the number in this exclusive group to 21.

“Before the Kepler space telescope launched, we 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.

“This knowledge informs the future missions that are needed to take us ever-closer to finding out whether we are alone in the universe,” he added.

In July last year, Kepler identified 4302 potential planets – of those, 1284 were determined as having a probability of more than 99 per cent of being planets. According to NASA, there’s still a good chance that an additional 1327 of the candidates are planets, but they do not yet meet the 99 per cent threshold, so will require further study. 

Of the nearly 5000 total planet candidates found to date, more than 3200 have now been verified, and 2325 of these were discovered by Kepler. 

Launched in March 2009, Kepler is the first NASA mission to find potentially habitable Earth-size planets. For four years, Kepler monitored 150,000 stars in a single patch of sky, measuring the tiny, telltale dip in the brightness of a star that can be produced by a transiting planet.

This latest boost in the number of known exoplanets “gives us hope that somewhere out there, around a star much like ours, we can eventually discover another Earth,” said Ellen Stofan, chief scientist at NASA Headquarters in Washington.