The Dog Days of Summer begin on July 3rd.  In ancient times, when the night sky was unobscured by artificial lights and smog, different groups around the world drew images in the sky by “connecting the dots” of stars.  The images drawn were dependent upon the culture:  The Chinese saw different images than the Native Americans, who saw different pictures than the Europeans.  These star pictures are now called constellations, and the constellations that are now mapped out in the sky come from our European ancestors.

They saw images of bears - (Ursa Major and Ursa Minor), twins - (Gemini), a bull - (Taurus), and others, including dogs - (Canis Major and Canis Minor).

The brightest of the stars in Canis Major is Sirius, which also happens to be the brightest star in the night sky.  In fact, it is so bright that the ancient Romans thought that the earth received heat from it.

In summer, Sirius, the “dog star,” rises and sets with the sun.  During late July Sirius is in conjunction with the sun, and the ancients believed that its heat added to the heat of the sun, creating a stretch of hot and sultry weather.

Today, dog days occur between July 3 and August 11.  Although it is certainly the warmest period of the summer, the heat is not due to the added radiation from a far-away star.  The heat of summer is a direct result of the earth's tilt, plus the heat in the Northern Hemisphere simply takes time to build to its maximum level.