As the earth rotates around the sun all year round, it passes streams of cosmic debris. The resulting meteor showers can light up the night sky from dusk to dawn, and if you’re lucky, you might catch a glimpse.
The next shower you might see are the Perseids. They are active from July 17th to August 24th and peak from Wednesday evening to Thursday morning or August 11th to 12th.
The Perseids light up the night sky when the earth encounters pieces of cosmic debris left by Comet Swift-Tuttle. The dirty snowball is 27 kilometers wide and takes about 133 years to orbit the sun. The last lap was in 1992.
During the peak of the display, between 160 and 200 meteors dazzle the earth’s atmosphere every hour. They race through the atmosphere at about 133,000 miles per hour and explode about 100 miles above them. The moon isn’t too full right now, which could make for good visibility, with showers being most active in the hours before dawn, according to the International Meteor Organization.
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Where do meteor showers come from
When you spot a meteor shower, you usually see the remains of an icy comet plummeting into the Earth’s atmosphere. Comets are like dirty snowballs: on their journey through the solar system, they leave behind a dusty trail of rocks and ice that lingers in space long after they have left. As Earth passes these cascades of cometary debris, the debris – which can be as small as grains of sand – penetrates the sky at such a rate that it bursts and creates heavenly fireworks.
A general rule of thumb for meteor showers: you never watch the earth turn into debris from a comet’s final orbit. Instead, the burning bits come from the previous passes. So for the Perseid meteor shower, you’re seeing meteors that were ejected when its parent comet, Comet Swift-Tuttle, was visited in 1862 or earlier, not from its last pass in 1992.
That’s because it takes time for debris to drift out of a comet’s orbit into a position where it intersects Earth’s orbit, according to Bill Cooke, an astronomer with NASA’s Meteoroid Environment Office.
The best way to see a meteor shower is to go to a location that has a clear view of the entire night sky. Ideally, it would be somewhere with dark skies, away from the city lights and traffic. To maximize your chances of seeing the show, look for a location that has an expansive, unobstructed view.
Parts of meteor showers are visible for a period of time, but they peak on some days from dusk to dawn. During these days, Earth’s orbit traverses the thickest part of the cosmic stream. Meteor showers can vary in their peak times, with some reaching their maximum for just a few hours and others for several nights.