Scientists have discovered an an exoplanet roughly the size of Earth orbiting Alpha Centauri B, the star nearest our sun.

Though the newly discovered planet has about the same mass as our own, its orbit is 25 times smaller, so a year on this planet passes in just 3.2 days, Wired.com has noted.

The newly discovered planet is too close to its sun to support known forms of life, with a surface temperature estimated at 1,200 degrees Celsius.

"Finding in our closest neighbor a one-Earth-mass planet really opens up the prospect for finding planets there in the habitable zone," said astronomer Stephane Udry of the University of Geneva, as cited by Wired.com.

The new planet is the lightest one ever found orbiting another star. Many of the exoplanets discovered so far have been gas giants.

Alpha Centauri is a triple star system that is our sun's closest neighbor, located only 4.4 light-years away.