Amateur astronomers working with the online citizen science project Planet Hunter have discovered two potential exoplanets, according to reports.

Since its launch last December, as many as 40,000 users from around the world have used scientifically-generated data collected by NASA's Kepler mission to help professional astronomers analyze light from 150,000 stars, with the hope of discovering Earth-like planets orbiting them.

One of the two newly-discovered bodies is two-and-a-half times the size of Earth and has a solid surface, leading to speculation that it may be a possible home for extraterrestrial life. The second is a gas giant more like Jupiter and orbits its parent star every 50 days.

Now astronomers at Yale University have officially announced the discovery of the first two potential exoplanets.

A paper, titled Planet Hunters: Two Planet Candidates Discovered by the Public using the Kepler Public Archive Data, with details of the discoveries, has been submitted to the journal Monthly Notices of the Royal Astronomical Society and will be published shortly.

The Kepler team has already announced the discovery of 1,200 exoplanet candidates and will further analyze the ones with the highest potential. The team had initially discarded the two found by the users of Planet Hunter, for various technical reasons. 

The two potential exoplanets were found in the first month of Planet Hunters' operations, using data the Kepler mission made publicly available. The Planet Hunter's team sent the top 10 candidates found by the citizen scientists, which included the two now recognized as potential exoplanets, to the Kepler team, who analyzed the data. The two candidates were flagged as potential planets by several dozen different users, as the same data was analyzed by more than one user.

Planet Hunter users are now sifting through the next 90 days of Kepler data in the hopes of adding to the count.