|"In this our life, exempt from public haunt, finds tongues in trees, books in the running brooks, sermons in stones and good in everything." Shakespeare, As You Like It|
Had Shakespeare lived in today's world - seeing streetlights as ubiquitious as the stars once were in his day - he might have penned, "solace in the shooting stars." In this day and age of too much artificial lighting, yet too little good judgement on how to use it, very few people have ever seen a starry sky with truly dark-adapted eyes. How about reserving the weekend beginning on Friday, August 9, for a date with the Perseid Meteor Shower? From the comfort of a chaise longue and a sleeping bag, but far away from pesky artificial lights, your unspoiled view of the heavens may count as the experience of a lifetime.
Though sporadic meteors (or shooting stars) adorn the sky on any given night of the year, meteor showers are usually annual events, occurring on certain dates. When Earth's orbit collides with the orbit of a comet, the stream of cometary debris burning up in the Earth's atmosphere results in a meteor shower. These showers tend to intensify after midnight.
The Perseids, probably the best known and most reliable of all meteor showers, are expected to peak before dawn's first light on August 12. It's probable that you'll see 50 to 100 meteors per hour. The Perseids are known for their relatively high number of trains, or meteor trails that linger for a moment or two.
A few days before and after peaking, the shower may well perform to near capacity, sometimes even featuring multiple peaks. Forecasting the peak (or peaks) and the intensity of a shower, even one as dependable as the Perseids, involves some guesswork. Sometimes the peak comes earlier or later than expected, or the shower may exceed or fall shy of its billing. With some synergy, comet rubble (meteroids) may spawn - like fish - at just the right time and place in its orbital stream, assuring us of a spectacular meteor shower, if not a storm.
Sometimes, a meteor hits the ground to become a meteorite. According to Bob Berman of Astronomy magazine, comet dust of meteor showers is much too flimsy to survive a fiery plunge into the Earth's atmosphere, and no known meteorite has come by way of a meteor shower. It's thought that meteorites are primarily the remains of asteroids (minor planets) - though apparently, chunks from the Moon and Mars land on Earth now and again.
Comet Swift-Tuttle, the supposed parent of the Perseids, orbits the Sun in roughly 130 years. Its eccentric orbit takes it a bit closer to the Sun than the Earth ever gets, but on the other end, the comet wanders deep into the icy realms of the solar system, just beyond the orbit of Pluto.
The meteor shower derives its name from the constellation Perseus, because the meteors seem to stream from this realm of the sky. But you needn't find Perseus to enjoy the show, because the Perseids streak all across the heavens, through any number of constellations. For instance, in a baseball game, every hit ball - if traced backwards - is found to originate from home plate. Likewise, astronomers track these meteors back to Perseus, the Perseids' "home base."
According to star lore, the Perseid Meteor Shower commemorates the time when Zeus, the king of the gods, visited the mortal Danae in the form of a Shower of Gold. As a result of their union, Zeus and Danae became the proud parents of Perseus.
|August's Star of the Month: Zubenelgenubi!|