Tracks and Tales
By Pamela Holz, Washington County Conservation Board Naturalist
Watching the skies has played an important role throughout history in cultures across the globe. Many of them tell stories of shapes they saw in the night sky. Some used the changes in the heavenly bodies as ways to foretell the future. All discovered they could use basic movements to establish a calendar and mark the seasons. Later, travelers found the sky to be a useful aid in figuring out where they were and where they needed to go.
Even today, the sky draws our attention. The commotion over the solar eclipse last August and the ?super blood blue moon? of January attest to this.
Fortunately, exciting events happen in the sky all the time. Rainbows, sun dogs, viewable planets, the northern lights, the Milky Way, and more stretch, form or travel across our skies on a fairly regular basis. Even falling stars can catch our attention, calling out to be wished upon.
Some of these events occur randomly, and you just need to be in the right place at the right time. But even more can be forecasted in advance. For example, look to the west right after sunset to spot bright Venus, with Jupiter higher and to the south. In addition, we are also in the midst of a meteor shower.
The Perseid meteor shower, which peaks August 12 and 13, is so named as its shooting stars appear to originate from the constellation Perseus in the northeast. While it may be the most popular meteor shower, it is not the strongest. That title goes to the Geminids. That display is our only shower which has its highest rates conveniently before midnight and can include some colorful trails. The downside to the Geminids is timing ? December.
Meteor showers occur annually when the Earth?s orbit transects the debris field left behind by a comet. In the case of the Perseids, Comet Swift-Tuttle is the source. This massive comet orbits the sun every 133 years and was last spotted in 1992. Some of you might remember a short burst of fear over a potential comet impact in 2126. Older measurements on Swift-Tuttle created this buzz. In 1992, scientists were able to take more precise measurements and thus, dismiss this concern.
Because of the angle of the comet?s path, when it reaches Earth?s orbit, it is traveling very fast. This results in the comet?s debris also traveling fast, at speeds of 37 miles per second. The Geminids, in comparison, travel at 22 miles per second. The Perseids high speed adds to the show, with potential long trails and the occasional fireball.
This year, the Perseids has the potential to put on a very big show. Gravity from Jupiter could mean up to 200 falling stars per hour. However, anyone viewing in the evening will face some washout from the moon. Best viewing will be after midnight, after the moon has set, and the Earth is facing directly into the debris field.
Anyone interested in learning more about the Perseid meteor shower or general celestial information, or just would like some company while viewing, can come out to Marr Park early on Sunday, August 12 to watch the skies. We?ll meet next to the mini-lake parking lot at 4 a.m.
Chairs or blankets to sit on are recommended. And we can make a few wishes.