NASA has identified the most Earth-like planet to date and while not much is known about it, scientists say the discovery represents the possibility of more planets like it.

Published in the journal Science, the new study does not know if Kepler-186f has a protective atmosphere, liquid water and other elements necessary for life. However, it is another exoplanet spotted by the Kepler Telescope that resembles our planet Earth.

"This is an historic discovery of the first Earth-size planet found in the habitable zone around its star," Geoffrey Marcy, an astronomer at UC Berkeley, told the Los Angeles Times. "This is the best case for a habitable planet yet found. The results are absolutely rock solid."

Study co-author Stephen Kane, an astrophysicist from San Francisco State, said Kepler-186f is about 500 light years from Earth. Since the Kepler Telescope was launched in 2009, it has spotted about 1,000 Earth-like planets.

"There seems to be a transition that occurs at about 1.5 times the Earth's radius, such that if the planet is larger, then it starts to develop a very substantial atmosphere very similar to what we see in the gas giant planets in our own Solar System," Kane told BBC News. "And so anything less than 1.5 is probably more like a rocky planet that we are familiar with."

Not much is known about the new exoplanet, but the planet orbits its star in what scientists have identified to be an ideal habitable zone. The distance Kepler-186f is from its star is not too close where the water would boil and not too far where the water would freeze.

"Even though it is orbiting a star which is very different from our Sun, the planet itself - both in terms of size and the amount of energy it is receiving from its star - is the most similar planet to our Earth that we've yet discovered," said Kane. "That is great news in terms of looking for planets which might actually be similar to the Earth, especially as the kind of star it does orbit - which is a very small star - are amongst the most common in the galaxy.

"And if all of these very common small stars have lots of terrestrial-sized planets in the habitable zone then that is very good news."