NASA HAS ANNOUNCED that its Kepler mission has found its first planet inside a habitable zone, where conditions appear to be able to support life.

The zone – nicknamed the Goldilocks zone as conditions are “just right” – holds a planet roughly two-and-a-half times the diameter of the Earth, named Kepler-22b. Nasa scientists believe the planet could have liquid water on its surface, and say it orbits a star that creates an internal temperature of about 22C.

Kepler 22-b is the smallest planet yet found to orbit in the middle of the habitable zone of a star similar to our sun, according to Nasa.

“This is a major milestone on the road to finding Earth’s twin,” said Douglas Hudgins, Kepler programme scientist at NASA Headquarters in Washington. “Kepler’s results continue to demonstrate the importance of NASA’s science missions, which aim to answer some of the biggest questions about our place in the universe.”

Irish astronomers are also excited by the discovery of the planet, which has an orbit of 290 days around a sun-like star that is slightly smaller and cooler than our Sun.

“Now that we’ve found an Earth-like habitable planet orbiting another star we find ourselves asking – does life exist there?” said David Moore, Chairman of Astronomy Ireland. “If life does exist elsewhere in the Universe, then Kepler-22b could be a possible home for it. The planet may also provide new home for us in the future.”

There is one drawback, however: Kepler-22b is located 600 light-years away.

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