Stargazers will have myriad opportunities to make their wishes this weekend, as the Perseids meteor showers reach their peak.
Named for the constellation the so-called shooting stars appear to fall from, these annual August wonders seem to radiate from Perseus, which was named after a Greek mythological hero. Its triangular shape is supposed to call to mind the picture of Perseus carrying the head of Medusa the Gorgon.
Universetoday.com reports "The Perseids [showers] are also sometimes referred to as the 'tears of St. Lawrence,' after the Catholic saint who was martyred on August 10, 258 AD. The Perseids have been noted by Chinese astronomers as far back as 36 AD, when it was recorded that 'more than 100 meteors flew thither in the morning.' The annual nature of the shower was first described by Belgian astronomer Adolphe Quételet in 1835."
The origins of meteor showers are much less romantic than their namesakes would imply. According to the website stardate.org, "Most meteor showers are spawned by comets. As a comet orbits the Sun it sheds an icy, dusty debris stream along its orbit. If Earth travels through this stream, we will see a meteor shower. Although the meteors can appear anywhere in the sky, if you trace their paths, the meteors in each shower appear to 'rain' into the sky from the same region."
Sean Tvelia, an astronomer, professor of physical science at Suffolk Community College, and one of the heads of the Montauk Observatory explained, "The earth is travelling through debris left by comets, and right now we're going through some pretty dusty trails." So, rather than the magical mystical phenomenon romantics envision, a meteor shower is little more than earth making its way through a big patch of space dirt.
Still, it's mighty pretty when the meteors streak across the sky on a summer's night. And they go quite fast. Meteoroids, also called shooting stars and falling stars, can travel at speeds of tens of thousands of miles per hour. That fast, they ignite from the friction of the atmosphere, some 30 to 80 miles above ground. (The rare meteors that actually hit the ground are called meteorites.)
The Perseid meteor shower is often deemed the most popular to occur during the year. An article by Richard Talcott on the website astronomy.com explains why: "This annual shower seemingly has it all: It offers a consistently high rate of meteors year after year; it produces a higher percentage of bright ones than most other showers; it occurs in August when many people take summer vacation; and it happens at a time when nice weather and reasonable nighttime temperatures are common north of the equator. No other major shower can boast all four of these attributes."
Viewers can see as many as 80 meteors per hour, and there's another plus listed by Talcott. Peak viewing this weekend will occur without the distraction (and light) of the moon. The waxing crescent moon will set just after 10 PM on Sunday night, meaning the shooting stars will have less light competition in the sky. Perseus rises in the northeast at around 11 PM.
You do have to look for them, though, Professor Tvelia emphasized. And it's not exactly a torrent of a shower most people might expect. One or two falling stars might streak across the sky per minute, and, since they could come from any direction, a measure of vigilance and patience is required.
Backyard stargazers don't need a telescope to see the shower, but darkness helps. Steer clear of artificial lighting, and be prepared to watch the sky during the early morning hours before 4 AM. Pre-twilight Sunday morning is the predicted best time to view the most spectacular aspects of the shower, but shooting stars will be visible throughout the night all week long.
Because the most vivid part of the shower happens at such a late (or early, depending on your night) hour, observatories don't often host meteor shower watching parties, Professor Tvelia reported. Instead, individuals are encouraged to find a dark spot with lots of open skies, bring a chaise lounge, relax, and wait.
"The best way to do it," he said, "is just get a lawn chair, lie down, and stare upwards."
While the showers are slated to peak this weekend, experts suggest beginning to watch for them a few days in advance. And, if you fall asleep and miss it Sunday, the showers will continue through August 24, with the number of shooting stars per hour diminishing as time goes by.