Recently Dr. Michael Gillon of the University of Liege in Belgium and a team of astronomers hypothesized since that approximately 2/3 of the stars in our neighborhood are red dwarf stars some of them might host inhabitable planets. To test this idea the researchers began to carefully monitor some nearby red dwarfs with a robotic telescope in Chile to see if any of them the have regular dips in brightness which indicate the presence of planets orbiting them.
This team of astronomers were delighted when a faint star in an infrared star catalogue showed regular dips in brightness indicating the presence of three planets. Followup observations by the European Southern Observatories' 8 meter telescope in Chile confirmed the presence of three Earth sized planets orbiting a star now known as TRAPPIST-1. This extremely faint red star is only slightly larger than the planet Jupiter and puts out 0.05% of the energy of our Sun. Two of its Earth sized planets orbit every 1.5 and 2.4 days receiving four and two times the radiation the Earth receives from our Sun. They are probably two hot to be habitable. The third Earth sized planet orbits farther away and thus might have life permitting temperatures on its surface.
The discovery of three Earth sized planets orbiting the extremely, cool, faint red dwarf star TRAPPIST-1 suggests the possibility of the presence of many more relatively nearby Earth like planets. The next generation of ground and space based telescopes will tell us about their surface conditions.