"Dog Days" of Summer Begin Today

The “Dog Days” of Summer officially arrive today. No, that’s not because I relented and turned on the air conditioners. Most people casually refer to the "Dog Days" as a period of hot and humid weather. But did you know that the dog days are a 40-day period which last from early July through mid-August?

The dog days of Summer run from July 3 through August 11 in the Northern Hemisphere and have to do with the star Sirius, known as “the dog star.” Sirius is the brightest star in the Northern Hemisphere other than the Sun, and it is found in the constellation Canis Major, thus the name “dog star.”

In the Summer, Sirius rises and sets with the Sun. During late July, Sirius is in “conjunction” with the Sun. The ancients believed that its heat added to the heat of the Sun, creating a stretch of hot and sultry weather. They named this period of time, from 20 days before the conjunction to 20 days after, the “dog days” after the dog star.

In ancient times, when the night sky was unobscured by artificial lights and smog, different groups of peoples in different parts of 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 (the big dog) is Sirius. The star can be seen prominently in the Winter in the Northern Hemisphere, adjacent to Orion the Hunter.
The conjunction of Sirius with the Sun varies somewhat with latitude. Also, the constellations today are not in exactly the same place in the sky as they were in ancient Rome. Although we are in the middle of the dog days of Summer right now, the heat is not due to the added radiation from a far-away star, regardless of its brightness. The heat of Summer is a direct result of the earth’s 23.5 degree tilt on its axis, meaning the Northern Hemisphere is tilted toward the Sun during the Summer.

So, the "Dog Days" of Summer have officially arrived as of today. We'll have a warm and dry day ahead with temperatures climbing well into the 80s. Showers and thunderstorms are expected late tonight and early tomorrow before another round arrives tomorrow afternoon. Daytime high temperatures will hold in the 80s through the rest of the week and the weekend.

Happy Dog Days!


Paul

Full Thunder Moon Arrives Just in Time for Mother Nature's Fireworks Show

I had company on my way to work this morning. Yes, the nearly Full Moon smiled directly at me from a fairly low angle above the horizon as I drove westbound along I-95 in the middle of the night. And what a sight it was. You, too, may have noticed the light of the Moon filtering into your window last night.

In case you’re wondering, the Full Thunder Moon happens at 2:52 this afternoon. The Full Thunder Moon is so named since thunderstorms are common during this time of the year. Another name for this month’s Moon is the Full Buck Moon. July is normally the month when the new antlers of buck deer rush out of their foreheads in coatings of velvety fur. Another name for this month’s Moon is the Full Hay Moon.

Full Moon names date back to Native Americans in what is now the Northern and Eastern United States. The tribes kept track of the seasons by giving distinctive names to each recurring Full Moon. Their names were applied to the entire month in which each occurred. There was some variation in the Moon names, but in general, the same ones were current throughout the Algonquin tribes from New England to Lake Superior.

A Full Moon rises at about the same time the Sun is setting. Since the length of daylight is about 15 hours and four minutes today, the Full Moon will rise later and set earlier this time of the year. In addition, the Full Moon will appear lower in the sky since it won’t be visible nearly as long as during the mid-Winter nights.

For example, the Moon rises at 8:23 this evening (99.4% full) and sets at 6:30 tomorrow morning (99.6% full). That means the Moon will be visible for ten hours and seven minutes. Conversely, six months from now in January when the amount of daylight is at a minimum, the Full Wolf Moon will appear higher in the sky and be visible for about 17-and-half-hours. That’s over seven hours longer than this time of the year!

We won't be able to see much of the Moon tonight since an approaching warm front will bring clouds, more humidity, and showers and thunderstorms late at night. Tomorrow will be quite warm and muggy with more showers and thunderstorms developing during the afternoon. High temperatures will climb into the mid-to-upper 80s once again. I suppose the Full Thunder Moon will come just in time for Mother Nature's Independence Day fireworks show of her own.

Paul