Things sure are heating up. Even in my home state of Minnesota (where it just stopped snowing two months ago), I have all the fans running full blast. That’s because we’ve officially entered the dog days of summer.
The dog days of summer are known as being the hottest period of the year, running from July 3 to August 11. However, the name has nothing to do with our beloved Fidos.
The name actually comes from Sirius, the brightest star in our sky. Sirius is known as the Dog Star and is the chief star in the constellation Canis Major. Dog days traditionally began when Sirius rose at the same time as sunrise (heliacal rising), causing Romans to attribute the extra heat to the meeting up of the two stars. (Due to shifts in the equinoxes, this is no longer happens, at least if I correctly understood all of the astronomy articles I’ve been reading.)
According to the Online Etymology Dictionary, the term dog days comes from the 1530s, when it was known in Latin as dies caniculares, translated from the Greek hēmerai kynades.