Perseid Meteor Shower: What Causes the Annual Sky Spectacle

What's causing those bright flashes of light at meteor shower's peak.

ByABC News
August 11, 2015, 3:20 PM

— -- When the Perseid meteor shower reaches its peak action early Thursday morning, as many as 100 meteors per hour will be visible streaking across the sky.

The meteors from this year's show are sure to create another dazzling spectacle that begins each year when Earth passes through a cloud of the Swift-Tuttle Comet’s debris, according to NASA, causing small bits of comet dust to enter our atmosphere at 37 miles per second.

The Perseid meteor shower is the result of space debris from the Swift-Tuttle Comet striking the Earth’s atmosphere. When the dust disintegrates, it creates the gorgeous bright streaks that light up the sky.

The meteor shower has been observed for at least 2,000 years. For the best viewing, NASA recommends looking toward the constellations Cassiopeia and Perseus in the northeastern part of the sky when the Perseids peak at 4 a.m. ET.