Discovered some 130 light-years from Earth, the planet is too dim to be viewed in the optical spectrum. But by analyzing its infrared emissions they were able to determine a few things about its chemical composition and its mass, which falls somewhere between four to seven times that of Jupiter. These kinds of starless planets aren't unheard of, but they are relatively difficult to detect when they are out there on their own. Astronomers usually detect planets outside our solar system by either observing its transit of its star or measuring the wobble of the parent star caused by the orbiting planet's gravitational pull.