Who hasn't heard of the Dog Star, Sirius - the most brilliant star in the heavens. Right now it rises in the east around 10 p.m., and can easily be identified because the famous belt of Orion points down and leftward to it.
As the brightest star in the constellation of the Big Dog, Sirius was considered bad news in the Roman Empire, when hit men sometimes sacrificed dogs when Sirius appeared. The Dog Star had better press in ancient Egypt; they believed an alliance between the sun and the brightest star caused summer's heat. Even today we still use the expression "Dog Days" to mean sultry weather.