As the weather and humidity in central Illinois make it feel more and more like the temperature is over 100°F outside, the IDHH is highlighting the proverbial “dog days” of summer. While the phrase “dog days” or “dog days of summer” might be somewhat familiar, just what are these days and how did this expression enter our cultural lexicon? From an astronomical point of view, the phrase refers to the annual phenomenon in which the bright star Sirius rises into the sky at the same time as the Sun. This heliacal rising allows viewers to see both the Sun and the Sirius star simultaneously, leading to the belief that Sirius intensified or added to the Sun’s heat. In the Northern Hemisphere, this simultaneous rising may be seen during the hottest months of the year, in July and August.
Hellenistic astrologers in the Mediterranean were aware of the star Sirius, calling it the “Dog Star” due to the way it followed the constellation Orion into the night sky. The sweltering and humid weather in the Mediterranean during these months would often cause people to fall ill, and so the connection was made between Sirius’ heliacal rising and its effect on the populations below. A variety of detrimental effects to human activities were attributed with Sirius’ rising such as lethargy, fever, and bad luck, as well as the belief that this hot period brought out madness in dogs, further reinforcing the notion of the “dog days”. While we may no longer blame a summer fever on the “dog days of summer”, there is no denying the potent influence of a heat wave in July to inspire lazy dreams of a nice afternoon spent on the water. Between numerous lakes and ponds, miles of river, and spots like Navy Pier on the shores of Lake Michigan, Illinoisians have plenty of ways to cool down during the hot summer.
Below are a few of our favorite items highlighting ways to enjoy the “dog days of summer” and beat the heat:
It’s the middle of summer and with the warm weather and school vacations, it’s peak season for outdoor activities. This time of the year, kids in Chicago take advantage of the city’s more than 500 parks, over 90 of which are featured in the Chicago Public Library’s Chicago Park District Records Photographs collection.
What better way to keep cool during the summer heat than at the pool? Chicago’s parks boast more than 70 pools across the city, just three of which are pictured below. As these photos suggest, pools have been an integral part of outdoor summertime activities in Chicago at least since the turn of the twentieth century.
On cooler days or when kids would prefer to stay dry, there are the Chicago Park District’s more than 300 playgrounds around the city. Beyond the slides, swings, merry-go-rounds, and more unusual features, the playground has long been a central place for after-school and summertime activities.
Being a landlocked state, Illinois is not known for seaside attractions. Illinois is, however, home to one of the largest bodies of water in North America, Lake Michigan, along which sits the Illinois Beach State Park and the Illinois Beach and North Dunes Nature Preserves. Pictured below are images provided courtesy of the Dunn Museum’s Lake County History in Postcards. The location is just an hour’s drive north of Chicago.