What is the Perseid meteor shower?

Everything you need to know about the annual Perseid meteor shower and how to watch it.
Learn more about meteor showers.

Transcript

The Perseid meteor shower peaks every August and is one of the best showers of the year with around 50 to 100 meteors per hour at a dark site. The Perseids are caused by debris from comet Swift-Tuttle. The comet’s 133-year orbit carries it out beyond Pluto. It last visited our inner solar system in 1992 and won’t be back again until 2125.

If you’ve never seen one before, you might be wondering: What is a meteor shower? Meteors are commonly called shooting stars, but they aren't actually stars at all. Meteors are streaks of light in the sky caused by dust and sand-sized rocks burning up as they hit Earth's upper atmosphere at very high speeds. Often over 100,000 km per hour. On a typical night from a dark location, you might be lucky enough to see up to 10 meteors per hour. But when the earth passes through the dusty debris that was left behind by a comet or asteroid, you will be able to see quite a bit more activity in the sky. We call this a meteor shower.

Since the Earth orbits around the Sun, meteor showers reoccur at about the same time every year as Earth passes through the debris again. Meteor showers are named after the constellation that contains the radiant of the shower. The radiant is where the meteors appear to emanate from. If you draw a line back along the meteors, all the lines will meet at the same point. This is an effect of Earth speeding through the comet debris. Meaning when you watch a meteor shower, you're seeing direct evidence of our planet orbiting the Sun.

All you need to watch a meteor shower is your eyes, patience, and a clear night. Typically, the best time to see a meteor shower is between midnight and pre-dawn, because that's when you're on the leading side of the earth moving right into the debris. By the way, if you've heard of meteoroids and meteorites, you might be wondering what the difference is. While in space, the object is called a meteoroid. The short moment while it's entering the atmosphere and burning up into that visible streak of light it’s called a meteor. And if any part of that object survives and lands on Earth, it’s then called a meteorite. And they look like this. To learn more about meteor showers follow the link in the description.