Scientists have now measured the spin of a supermassive black hole, describing the rate in terms of the energy needed to sustain the spin. These black holes are thought to occupy the center of virtually every galaxy.
Astronomers have calculated that 6 percent of our galaxy's most common type of star probably host temperate, Earth-sized planets, meaning that a habitable alien Earth could be just a dozen light years away.
Recent work suggests that the upper limit to the largest gatherings of galaxies is about 1.2 billion to 1.5 billion light-years across. The structure that the team reports is nearly four times this theoretical limit.
Experts say Pyongyang is years from even having a shot at developing reliable missiles that could bombard distant targets, though it did gain attention and the outrage of world leaders with its first successful launch of a three-stage, long-range rocket.
Secret shuttle launch goes off without a hitch Tuesday. But what is the secret mission of X-37B? The robotic, military shuttle spent seven months in space during its last mission. It could be spying on terrorists, speculates one scientist.