Perseid Meteor Shower

Besides planets like the Earth which orbit the sun, there are also things called comets that orbit the sun, too. Comets are smallish chunks of rock and ice that have no atmosphere. As they hurdle through space, some of the rock and ice break away and leave a streak of debris behind the comet. When the Earth passes through that strip of debris, some of it is attracted by the Earth's gravity and is pulled towards us, burning up in the atmosphere. The result is a meteor, often called a "shooting star." A meteor can streak through the atmosphere at any time.

During the course of Earth's yearly trip around the Sun, we pass through the debris fields left behind by several different comets, and each of these produce an increased number of meteors, called a "meteor shower."

All meteors originate from within our solar system, that grouping of things that is immediately orbiting our own star which we call the Sun. All other stars in the sky are a very far distance away from us, measured in trillions of miles and more. However, from our vantage point it appears that the meteors are coming from a point among those far-away stars even if they aren't. It's like seeing your child across the yard, running towards you, while a distant mountain is in the background; the child isn't coming from the mountain, just the other side of the yard, but the mountain is there in the background, nonetheless.

^{• SCREENSHOT FROM STELLARIUM, ENHANCED BY ME •}

The best meteor shower each year is one that appears to be coming from the direction of the constellation Perseus (pronounced like the English words: pear - see - us), so the meteor shower is named the Perseids (like: pear - see - ids). That grouping of stars was fancied as the hero Perseus from Classical Greek literature. The Perseids are caused by debris left from the passage of Comet Swift–Tuttle (named for the two gentlemen who discovered it), which orbits the Sun once every 133 years. The Earth passes through the path of this comet every year in mid-August, with the 12th and 13th bringing the most visible meteors. For a week or two on each side of this date, though, Perseids might be seen, but there will be more around the peak dates.

The constellation of Perseus is not particularly easy to see unless one is in a location with very dark skies. However, another constellation, Cassiopeia (pronounced: cass - ee - oh - PEE' - ah) is just above Perseus and much easier to find! Just look for a grouping of stars shaped like the letter "W." In Greek mythology, Cassiopeia was a queen who wed her daughter, Andromeda, to Perseus after he saved the kingdom from a sea monster.

Meteors can appear anywhere across the sky. If one draws an imaginary line backwards, however, the Perseids will all appear to be originating from a spot near the cap of the hero. This apparent point-of-origin is called a radiant. If the imaginary line drawn backwards does not line-up with the radiant, then you have spotted a random meteor that is not part of the regular Perseid stream.

The best time to watch for meteors is always after the midnight-1am timeframe. The reason for this is because between then and dawn, the Earth is positioned so that it is pointing into the stream, instead of away from it. To visualize why, imagine being in the back seat of a car driving down a road — if you look out one window, you will see the pretty countryside, but miss any cars that are passing you; but, looking out the other window, you will see all those cars!

To spot the most meteors, use a chair that reclines backwards, or lie on a blanket, where you have as unobstructed view of the sky as possible. Just be sure to use mosquito repellant!

While you're out there, keep a watch for the bright star Capella rising in the northeast. Also worth looking for is a fuzzy little group of seven stars called the Pleiades (pronounced: PLEE' - ah - dees). This little star cluster is shaped a bit like a dipper, causing many people to mistakenly call it the "Little Dipper," but the true Little Dipper is a separate constellation, and much larger than this tiny group! The Pleiades are sometimes called the "Seven Sisters," and appear in the mythological stories of ancient Greece. This Japanese name for this star cluster is "Subaru," and the cluster is depicted in stylized fashion as the logo of the automobile manufacturer that has adopted the cluster's name as their own company name.

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