Sky Watch: The origin of summer 'dog days'

Other Columnists As much of 's Northern Hemisphere bakes in the heat of summertime, you'll hear someone refer to this time of year as the "dog days of summer." Now one might guess that this term comes from the seemingly lethargic behavior of our canine companions in the late-summer heat, but then one would be barking up the wrong tree. No; its origin lies among the stars. Early sky watchers kept close watch on the heavens in an attempt to correlate celestial and terrestrial activity and noticed that, during this hot season, the star Sirius rose around the same time as the sun, and the two moved across the daytime sky together. Sirius -- the most luminous star in the night sky -- is known as...