Scientists have only searched through a tiny fraction of our galaxy, and with the fast advances in technology, we can expect many more interesting discoveries in the future. But for now, check out the handy infographic below, courtesy of Space.com, displaying all known types of alien worlds.
The dwarf star HD 40307, located 44 light-years from Earth, hosts a system of six planets, including one at an orbital distance just right to support life as we know it. The planet could theoretically be photographed by next-generation space satellites now on the drawing board.
Astronomers find star with three super-Earths - Yahoo News
This global view of Jupiter's moon, Io, was obtained during the tenth orbit of Jupiter by NASA's Galileo spacecraft on 19 September 1997 at a range of more than 500,000 km (310,000 miles). Io (which is slightly larger than Earth's moon) is the most volcanically active body in the solar system. Colors are enhanced. Credit: NASA/JPL/University of Arizona