A ground-based telescope has helped scientists discover an exoplanet twice the size of our Earth. Finding a planet outside our solar system had always been the work of space telescopes. This is the first time that an exoplanet was discovered with the help of a ground-based one.

The exoplanet 55 Cancri e was seen through the Nordic Optical Telescope located in La Palma, an island off Spain, as the celestial body went past its parent star, which caused the star's brightness to dip. Astronomers also learned that the exoplanet is twice the size of the Earth and orbits another star similar to the sun.

55 Cancri e, first identified by a space telescope in 2004, has a diameter of about 16,000 miles, which is twice greater than that of the Earth. Even though it is bigger than the Earth, the exoplanet is still smaller than some other planets in our solar system. Scientists claim that the planet is not habitable; however, its position, size and revolution around a sun-like star makes it similar to planets that can support some sort of life.

Astronomers suggest that 55 Cancri e is very close to its host star. The exoplanet's dayside temperature can reach over 3,100 degrees Fahrenheit, or 1,700 degrees Celsius, which is hot enough to melt metal. The host star of the 55 Cancri e is not very far from the Earth and is located about 40 light years from our planet and is also visible to the naked eye.

Ernst de Mooij of Queen's University Belfast in the United Kingdom, who is the lead author of the study, says that their observations indicate that astronomers on Earth can actually notice the transits of small planets around sun-like stars with the use of telescopes based on ground.

"It's remarkable what we can do by pushing the limits of existing telescopes and instruments, despite the complications posed by the Earth's own turbulent atmosphere," said Ray Jayawardhana of York Univerity in Canada, who is the co-author of the study. "Remote sensing across tens of light-years isn't easy, but it can be done with the right technique and a bit of ingenuity."

De Mooij adds that the latest discovery is very important as it may help scientists find even more exoplanets with the help of ground-based telescopes.