Astronomers at Caltech announced this week that evidence suggests a ninth planet could exist in the outer reaches of the Solar System. Unexpected alignments in the orbits

Astronomers at Caltech announced this week that evidence suggests a ninth planet could exist in the outer reaches of the Solar System. Unexpected alignments in the orbits
A piece of history for today’s image. These spidery lines are astronomer Percival Lowell’s sketches of canals on Mars, dated from the late 1890’s or
1. Vulcan The planet Vulcan has a history that’s even older than Star Trek. And almost as entertaining. In the 1840’s, astronomers were puzzled by perturbations