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Nation

Smallest planet yet found outside solar system

An artist’s conception of the tiny new planet, which has been named Kepler-37b.

Reuters

An artist’s conception of the tiny new planet, which has been named Kepler-37b.

LOS ANGELES — Astronomers searching for planets outside our solar system have discovered the tiniest one yet — one that’s about the size of our moon.

But hunters for life in the universe will need to poke elsewhere. The new world orbits too close to its sun-like star and is too sizzling to support life. Its surface temperature is an estimated 700 degrees Fahrenheit. It also lacks an atmosphere and water on its rocky surface.

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University of California, Berkeley astronomer Geoff Marcy, one of the founding fathers of the planet-hunting field, called the latest find ‘‘absolutely mind-boggling.’’

‘‘This new discovery raises the specter that the universe is jampacked, like jelly beans in a jar, with planets even smaller than Earth,’’ said Marcy, who had no role in the new research.

It’s been nearly two decades since the first planet was found outside our solar system. Since then, there’s been an explosion of discoveries, accelerated by NASA’s Kepler telescope launched in 2009 to search for a twin Earth. So far, 861 planets have been spotted .

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