Scientists have discovered an "extremely cold" new planet about the same mass as Earth, and the same distance from its host star as our planet is from our Sun.
The planet is likely far too cold to be habitable for life as we know it because its star is very faint, said the study published in the Astrophysical Journal Letters.
Bur the newly discovered planet, called OGLE-2016-BLG-1195Lb, may aid scientists in their quest to figure out the distribution of planets in our galaxy.
The planet was discovered through a technique called microlensing that facilitates the discovery of distant objects by using background stars as flashlights.
"This 'iceball' planet is the lowest-mass planet ever found through microlensing," said lead author of the study Yossi Shvartzvald, a NASA postdoctoral fellow based at NASA's Jet Propulsion Laboratory, Pasadena, California.
The researchers believe that OGLE-2016-BLG-1195Lb is nearly 13,000 light years away and orbits a very small star — just 7.8 per cent of the mass of our Sun.
It could be a brown dwarf, a star-like object whose core is not hot enough to generate energy through nuclear fusion.
Alternatively, it could be an ultra-cool dwarf star much like TRAPPIST-1, which NASA's Spitzer space telescope and ground-based telescopes recently revealed to host seven Earth-size planets.
Those seven planets all huddle closely around TRAPPIST-1, even closer than Mercury orbits our Sun, and they all have potential for liquid water.
But OGLE-2016-BLG-1195Lb, at the sun-Earth distance from a very faint star, would be extremely cold — likely even colder than Pluto is in our own solar system, such that any surface water would be frozen, the researchers said.