NASA announced on Wednesday that its Spitzer Space Telescope has revealed the "first known system of seven Earth-sized planets around a single star." Three of the planets are located in what is known as a "habitable zone," the region around the group's parent star. This is the area where a rocky planet is most likely to have liquid water.

The planetary system is located 235 trillion miles (40 light-years) from Earth in the constellation Aquarius.

Science has long been looking to discover if we truly alone in the universe. This discovery is a "significant piece in the puzzle of finding inhabitable environments," NASA's associate administrator of the agency's Science Mission Directorate, Thomas Zurbuchen, said.