By Vinita Domier

The Perseid meteor showers are popular to watch because they occur in August (when the nights are relatively warm) and there is an average of 60 meteors per hour. Some of them even streak across the sky in long and colorful trails. This year’s celestial show peaks Saturday and Sunday, with the chance of seeing 50 to 100 meteors per hour.

Meteor showers occur when the revolving Earth passes through a stream of debris left in the wake of a comet during its perihelion, or closest approach to the sun. As a comet — often described as a “dirty snowball” — approaches, some of its gases vaporize, carrying dust and tiny fragments. These particles continue to orbit around the sun in the same orbit as the parent comet. When Earth goes through the point in space where the two orbits intersect, it results in annual meteor showers. Perseid meteor showers are attributed to Comet 109P/Swift-Turtle, which makes a complete orbit every 130 years.

Meteors are often mislabeled as shooting or falling stars. Astronomically speaking, meteors are the luminous streaks in the sky caused by debris particles. When the particles are in space, they are called meteoroids, and if any parts survive Earth’s atmosphere and land on the ground, they are known as meteorites. As meteoroids enter the Earth’s atmosphere from interplanetary space at high speeds, they are vaporized because of friction with air molecules. The light caused by these glowing vapors moves through the sky like a fast-moving star, forming visible trails and streaks.

There are eight major meteor showers that occur during the course of the year. Even though meteors have real parallel motions and are visible anywhere in the sky, their apparent direction of motion is away from a specific area in the sky called “the radiant.” These are named after the constellation from which they appear to radiate. Thus, Perseid meteor showers radiate from the Perseus constellation.

The best times to see meteor showers are between the midnight and sunrise closest to their peaks. More meteors will be visible after midnight because the radiant will be higher in the sky.

Adding to the show will be viewings of Saturn and Mars, which will be low in the west-southwest an hour after sunset, along with the bright star Spica. On Tuesday, the three objects formed an equilateral triangle. Golden yellow Saturn will be distinct from red-orange Mars, while blue-white Spica will contrast with both planets. Mars will pass between Saturn and Spica on Monday and Tuesday, with the three forming a nearly straight line.

Jupiter will rise around 2 a.m. local time in early August, just north of the bright orange star Aldebaran in the constellation Taurus the bull. Even brighter than Jupiter will be Venus when it rises more than three hours before the sun and dominates the morning sky.

To watch the meteor showers, all you need is a reclining chair or blanket to lie on. Point your toes eastward and look halfway up the sky. Make sure you have an unobstructed view of the sky and look in all directions. Viewing from a dark sky location, away from city lights, will enhance the experience. Also, bring insect repellent, as well as a red-filtered light or a flashlight covered with a paper bag to maintain night vision.

Happy viewing!

— Explorit Science Center is at 3141 Fifth St. and features a hands-on science exhibit open to the public the first full weekend of the month from October to August. For more information call (530) 756-0191 or visit http://www.explorit.org, or “like” us on Facebook at www.facebook.com/explorit.fb.

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