Read More: HowStuffWorks
One of the most captivating star systems beyond the solar system is in our galactic backyard. It may be a common red dwarf star, but the exoplanets it possesses are anything but ordinary. In fact, new observations have shown that the alien worlds of TRAPPIST-1 may be very special indeed. Located 40 light-years from Earth, TRAPPIST-1 is a mini version of our solar system. Orbiting the ultracool red dwarf are at least seven known small exoplanets of Earthlike dimensions, three of which orbit their star in the habitable zone. That's the area around a star at which it's neither too hot nor too cold for liquid water to exist on an exoplanet's surface. The discovery of any habitable zone exoplanet, particularly small and rocky ones, has implications for the possibility of finding extraterrestrial life. But simply finding worlds orbiting inside a small star's habitable zone doesn't mean those exoplanets are truly habitable. The zone just provides a guide as to where to look. The chemistry for life inside those exoplanetary atmospheres (if they even have atmospheres) need to be studied before an exoplanet can truly be considered to possess life-giving qualities. Now astronomers have begun that process for the worlds orbiting TRAPPIST-1 and deduced that they may contain water. Lots and lots and lots of water.