Scientists discover 15 new planets orbiting red dwarf stars

Scientists have announced the discovery of 15 new planets orbiting small, cool stars near our solar system. The stars these planets are orbiting are called red dwarfs. The scientists say that one of the new planets is a "super-Earth" that could harbor liquid water on its surface.

One of the brightest of the red dwarf stars that have been discovered to have orbiting planets is called K2-155 and it is about 200 light years from Earth. This star has three transiting super-Earths that are slightly bigger than our planet. The outermost of those three planets is dubbed K2-155d and has a radius 1.6 times the Earth.

That planet is thought to be in the host star's habitable zone. The findings the scientists have made are based on data from the Kepler spacecraft's second mission and follow-up observations from ground-based telescopes including the Subaru Telescope in Hawaii and Nordic Optical Telescope in Spain. Scientists say that K2-155d could potentially have liquid water on its surface based on three-dimensional global climate simulations.

The research team lead Teruyuki Hirano from the Tokyo Institute of Technology Department of Earth and Planetary Sciences says that in the simulations made by the team they assumed the composition of the planet was Earth-like. He points out there is no guarantee that is the case.

Scientists say that one of the key findings here is that planets orbiting red dwarf stars have similar characteristics to planets orbiting solar-type stars. Hirano also points out that red dwarf stars are just beginning to be investigated and are "exciting" targets for exoplanet research.