During the late 60s and early 70s my father loved to take his family on road trips. Long road trips. California to Minnesota and back. Virginia to New Mexico and back. Not once did we ever go “as the crow flies.” We criss-crossed states, visiting distant relatives and interesting new places. One of the most vivid memories from those trips was the prolific number of bugs that were smashed on the windshield of my Dad’s 1973 Dodge Dart. I remember laying on the floorboards in the back of the car (before the days of child safety seat laws) listening to the orchestra of sounds as my dad drove the nighttime highways of US 80 and 35 in Iowa; tires making their steady thrumming noise against the asphalt, the clicking of the blinkers as my dad changed lanes, and the steady rhythm of endless bugs making kamikaze attacks against the windshield at 80+ miles per hour. Their soft but staccato impacts sounded similar to rice krispies in milk. Every once in awhile there would be an enormous deluge of impacts, sounding like a disjointed drum roll. Obviously, we had just flown through a swarm or cloud of bugs. These swarms would add so much ‘stuff’ to the windshield that my dad had to immediately use the windshield wiper to clear his view. I remember recoiling as I saw the effects that the wipers and washer fluid had on the accumulation of bug matter, at first smearing and streaking the remains of so many bugs across windshield before creating fan shaped zones that were bug (and guts) free.
As our planet Earth moves through the solar system, cruising around the Sun at a leisurely 67,000 miles per hour, it too encounters relatively bug-like objects that collide with the upper atmosphere at collective speeds of over 130,000 miles per hour. These mostly tiny objects are usually between the size of a grain of sand or rice or more rarely, the size of a golf ball. The Earth is continuously peppered with space matter, gaining on average over 100 tons a day. Although we cannot see them occurring in the daytime, we can usually see on average one of these objects entering the atmosphere every 15-20 minutes at night. These are typically called ‘shooting stars’ but in fact have nothing to do with stars.
Along the 365.256363004 day journey around the Sun, the Earth also occasionally encounters a ‘swarm of bugs.’ Or rather, a swarm of solar system debris that comes to us from comets. One comet in particular, known as Comet Swift-Tuttle makes a 133 year orbit of the Sun, spitting out enormous amounts of dust and debris as it approaches the Sun. On one of its passes as it entered our solar system about 1000 years ago, it left enough debris in its wake that Earth has been passing through it every year since and has provided us with our annual Perseid Meteor Shower.
Sometimes called the Tears of St. Lawrence because of his martyrdom on August 10th, the Perseids Meteor Shower occur from mid-July to mid-August but their ‘peak’ occurs on the night/early morning hours of August 11/12. The following nights/early mornings of August 12/13 and 13/14 will also likely yield a decent showing because of the later arrival of the Moon. Typically, the expectation is to see 100 or more per hour, but light pollution will severely affect the number of Perseid meteors visible. Viewing from a suburban backyard will likely not yield good results as man-made light pollution makes it nearly impossible to see anything but the brightest objects. It is highly recommended to go somewhere away from population centers and find a relatively dark sky to observe the meteor shower. The Moon will be present and usually spoils the event, but its post midnight arrival and its slender phase gives us hours of unfettered observing of the year’s best meteor shower.
Called the Perseids because the radiant, or the invisible point in the sky where the meteors will appear to emanate from is in the constellation of Perseus the Hero. In spite of their apparent origin, the meteors themselves will be visible across the entire sky, and because of the chemical components of the particles the ‘shooting stars’ will appear in a great range of colors as they vaporize 60 miles above our heads in the upper atmosphere.
The best time to watch the Perseids is after midnight. Look to the north east and seek out the ‘M’ or ‘W’ asterism of stars of the constellation of Cassiopeia. Just below her you will see the bright stars of Perseus. While this is where the radiant is, the meteors will appear in all parts of the sky, at an average rate of 1 per minute, more or less depending on how dark your sky is. I cannot stress the value of dark skies enough. The darker the skies, the more of it becomes visible.
Perhaps the best way to enjoy this annual celestial treat is to find that dark sky spot somewhere out where you go to get away from people. For me, I will be visiting a spot about 40 miles from the gulf coast, out in farming country where the skies are always pretty dark. For the spartan observer, just a pair of eyes will do. But comfort will make the experience more enjoyable. Bringing a blanket to lay on the ground will make it easier to continually be looking up, but will also allow you to see more of the whole sky.
If you can make it to the predawn hours, the glowing shower of celestial dust will be joined by the planets Jupiter and Venus, creating a visual crescendo that will abruptly end when the Sun makes its appearance. If this years Perseid meteor shower is a let down, there’s always next year.
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