AE Aurigae is the stellar equivalent of a runaway train. It’s moving far faster than any of the other stars around it — the result of a complicated “collision” about two million years ago. The star is in Auriga, the charioteer. The constellation is low in the northeast at nightfall, but climbs into good view by about 8 o’clock, and soars high across the sky later on. Auriga’s brightest star, Capella, is one of the brightest in the night sky, so it’s easy to pick out. More about Capella tomorrow. AE Aurigae, on the other hand, is so faint that you need binoculars to see it. But that’s only because of the star’s distance — about 1500 light-years. The star itself is a true stunner — about 30,000 times brighter than the Sun. It probably was born with a massive companion. But a couple of million years ago, the system ran into another massive binary. The stars themselves didn’t collide. But they passed so close together that the two systems split apart. One star from each binary stuck togeth
