... Discovered in 1963, astronomers were astounded that such objects could be visible across billions of light-years, as this implies they must emit prodigious amounts of energy. ... Comet Ikeya Zhang Brightens . ... A large, elliptical galaxy dominates this hypothetical cluster's central region surrounded by a swarm of member galaxies. ... Here are the true colors of planet Earth. ... Although the crawlers pack over 5,000 horsepower, their top speed is less than two kilometers per hour when fully...