![]() Those high velocities give each particle a lot of kinetic energy, which converts to heat due to friction in the upper atmosphere. Typically they're no bigger than big sand grains, and something the size of a pea can create a meteor that's dramatically bright. The little nuggets in Grape-Nuts cereal are a close match to the size of particles that typically create meteors in our atmosphere.ĭerived from the Greek word meteoros (meaning "high in the air"), meteors are bits of interplanetary debris that slam into Earth's upper atmosphere at speeds of 30 to 70 km (20 to 45 miles) per second! And although some meteors look bright enough that it seems you can almost touch them, actually they occur very high up, at altitudes of 80 to 120 km (50 to 75 miles).īecause they're arriving so fast, it doesn't take a very large particle to make a dramatic flash. The rarest of these, called a bolide, shatters into pieces during its rapid descent. These "shooting stars" can range in brightness from tiny blips just at the limit of visibility to dramatically bright fireballs that outshine Venus and light up the nightscape around you. John Van't Land / If you look up into a dark, Moonless night sky from a location far from city lights, you'll see brief streaks from meteors a few times every hour. Unfortunately, the popular Perseid and Geminid showers will be spoiled by bright moonlight.Ī Geminid heads for the horizon above "First Canyon", east of Gallup, New Mexico, on December 13, 2017. Sky & Telescope predicts that the two best meteor showers in 2019 will be the Quadrantids in early January and the Eta Aquariids in early May. ![]()
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