Mira, The Tail Star

We’ve been watching this thing for four centuries, and we only now noticed it had a tail, as Nature reports. A really long tail:

Astronomers have found an unexpected treat on a star first described more than 400 years ago – the streak of a 13-light-year-long tail.

Seibert says that Mira’s “shockingly huge” tail gives scientists valuable insight into the chemical evolution of galaxies. Stars such as Mira generate most of the midweight, but exactly how the elements are produced isn’t clear. Mira’s tail spreads out this process by putting the older material at the back of the tail and the newer material at the head, with the oldest part of the tail some 30,000 years old. “Now we’ll be able to tell at what rate these elements are being generated,” says Seibert. “It’s going to take years to decipher. But this discovery gets us started.”