Astronomers using the Gemini North telescope on Mauna Kea in Hawaii believe that they have captured the first image of an alien planet in orbit around a star that is similar to our Sun.

The planet in the image is 500-light years from earth and is eight times bigger than Jupiter, the largest planet in our solar system. The planet also lies more than ten times further from its star than the Sun does from Neptune, which is puzzling to the scientists.

The likelihood of a chance alignment between the planet and the star, which is younger than our Sun, is thought to be small. Nevertheless, it may take up to two years for the astronomers to verify that they are moving through space together.

The star, called 1RXS J160929.1-210524, is much younger than our Sun, but is similar in mass.

In a paper submitted to the Astrophysical Journal Letters, David Lefrenicre, a University of Toronto scientists, said: "This is the first time we have directly seen a planetary mass object in a likely orbit around a star like our Sun. If we confirm that this object is indeed gravitationally tied to the star, it will be a major step."

The only planet-like bodies that have been observed outside of our solar system are either free-floating in space or orbit brown dwarfs.

The distance of the planet from the star, if proven to be companion objects, will come as a surprise to the scientific community. It may also pose some challenges to current theoretical models of planet and star formation.