Sky-watchers are set to make a lot of wishes this week as the heavens open up with a flurry of shooting stars. The Perseid meteor shower is considered the "Old Faithful" of cosmic sky shows, peaking like clockwork every year on August 12 and 13.

The Perseids grace our skies when Earth plows into a stream of fragments—ranging in size from sand grains to boulders—left behind by a comet. These particles slam into the atmosphere at speeds of 100,000 miles (160,000 kilometers) per hour, causing the meteors to burn up in the upper atmosphere. The momentary streak created across the overhead skies is also known as a "shooting star."

At the same time each year, Earth passes through the dust trail of