Today is the 400th anniversary of the discovery of the first variable star, named Mira after the Latin word for "wonderful". Mira was discovered in the constellation of Cetus by David Fabricius, a Dutch/German astronomer, named David Fabricius on August 13th, 1596. A variable star is one which brightens over a period of time, eventually becoming visible to the naked eye, before dimming again.
Mira's anniversary coincides with the annual meteor shower known as the Perseids.
