A tiny exoplanet, called UCF-1.01, has been found 33 light years away from earth, according to a Nasa report.
The planet was discovered by an international team of astronomers, using Nasa's Spitzer Telescope. They told reporters that it is two-thirds the size of earth, and possibly the nearest world to our solar system that is smaller than our own planet.
"We have found strong evidence for a very small, very hot and very near planet with the help of the Spitzer Space Telescope," said Kevin Stevenson from the University of Central Florida, Orlando. "Identifying nearby small planets such as UCF-1.01 may one day lead to their characterisation, using future instruments."
Scientists made the discovery by accident, while studying a Neptune-sized exoplanet orbiting a red dwarf star. Analysing the Spitzer data, astronomers noticed periodic drops in the amount of infrared light emanating from the star, which suggested that a second planet might be circumnavigating it.
Further analysis revealed that a second planet was indeed orbiting the star, blocking out a small fraction of its light.
"I could see these faint dips in the starlight and I wanted to determine their source. I knew that if these signals were periodic, they could be from an unknown planet," Stevenson added.
The astronomers' study, published in the Astrophysical Journal, found that the diameter of planet UCF-1.01 was approximately 5,200 miles, two-thirds the size of earth. Astronomers also found that the UCF-1.01 is quite close to its own star - so close, in fact, that the planet orbits its star in just 1.4 days.
The UCF-1.01's surface temperature is more than 1,000 degrees Fahrenheit, the reason for its lack of atmosphere. The planet could have a volcanic surface because of its extremely close orbit.
Astronomers have found some clues about another tiny planet orbiting the same star. They claim further studies will help them know more about it.
"I hope future observations will confirm these exciting results, which show Spitzer may be able to discover exoplanets as small as Mars," said Michael Werner, Spitzer project scientist at Nasa's Jet Propulsion Laboratory in Pasadena.
"Even after almost nine years in space, Spitzer's observations continue to take us in new and important scientific directions."