Nasa have announced the discovery of Kepler-22b, a planet 600 light-years away from Earth which is in a habitable zone, an area that is within the 'sweet spot' in terms of distance from a star allowing for the existence of water in its liquid form.
The planet is the first that the Kepler spacecraft has discovered within this habitable zone.
"This is a major milestone on the road to finding Earth's twin," Douglas Hudgins, a Kepler program scientist stated.
"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."
Kepler-22b has a radius 2.4 times that of Earth's and orbits it sun-like star every 290 days, while enjoying a very accommodating temperature of approximately 72 degrees Fahrenheit.
Nasa is still not sure if Kepler-22b is composed or rock, gas or liquid.
A scientist at the NASA Ames Research Center who's on the Kepler team, Steve Howell, informed The Huffington Post that the most exciting discoveries are still to come.
"It's tremendously exciting," said Howell. "We're moving out to orbital periods that are nearly and equal to the Earth, and that means very soon we're going to be finding [planets] very near the earth, what we'd call true earth analogs. We'll be there. We'll be there probably within a year, very easily."