Most of the credit for these discoveries goes to the Kepler space telescope, which has discovered roughly 3500 planets and 4500 planetary candidates. In the wake of all these discoveries, the focus has shifted from pure discovery to research and characterization.

In this respect, planets detected using the Transit Method are especially valuable since they allow for the study of these planets in detail.

For example, a team of astronomers recently discovered three Super-Earths orbiting a star known GJ 9827, which is located just 100 light years (30 parsecs) from Earth.

The proximity of the star, and the fact that it is orbited by multiple Super-Earths, makes this system ideal for detailed exoplanet studies.

The study, titled "A System of Three Super Earths Transiting the Late K-Dwarf GJ 9827 at Thirty Parsecs", recently appeared online.

The study was led by Joseph E. Rodriguez of the Harvard-Smithsonian Center for Astrophysics and included members from The University of Texas at Austin, Columbia University, the Massachusetts Institute of Technology, and the NASA Exoplanet Science Institute.

As with all Kepler discoveries, these planets were discovered using the Transit Method (aka. Transit Photometry), where stars are monitored for periodic dips of brightness.

These dips are the result of exoplanets passing in front of the star (i.e. transiting) relative to the observer. While this method is ideal for placing constraints on the size and orbital periods of a planet, it can also allow for exoplanet characterization.

Basically, scientists are able to learn things about their atmospheres by measuring the spectra produced by the star's light as it passes through the planet's atmosphere.

Combined with radial velocity measurements of the star, scientists can also place constraints on the planet's mass and radius and can determine things about the planet's interior structure.

For the sake of their study, the team analyzed data obtained by the K2mission, which showed the presence of three Super-Earths around the star GJ 9827 (GJ 9827 b, c, and d).

These three exoplanets are especially interesting because the larger of the two have radii that place them in the range between being rocky or gaseous. Few such exoplanets have been discovered so far, which makes these three a prime target for research.