What are the differences between asteroids, meteoroids, meteors, and meteorites? Plus, how do you find a meteorite? Meteorites that fall to Earth are the next best thing to space missions. Extraterrestrial material comes to us, instead of the other way around! Learn more …
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To put it simply, asteroids, meteoroids, meteors, and meteorites are just different types of “space rocks.”
- The largest rocks are called asteroids. Think of asteroids like minor planets which orbit around the Sun just like Earth.
- Over time, these asteroids break down into smaller particles of rock called meteoroids. Meteoroids orbit our Sun, too.
- When one of those meteoroids enters the Earth’s atmosphere and vaporizes, it is called a meteor—or, “shooting star.” The meteor heats up and makes the air around it glow. We see a streak of light. Scientists think that up to 10,000 tons of meteors fall on the Earth each day, but most are no bigger than a speck of dust.
- Most meteors burn up entirely in Earth’s atmosphere, but if a meteor survives its passage through the Earth’s atmosphere and lands on Earth’s surface, it’s called a meteorite. Meteorites range in size from tiny pebbles to boulders.
Some planets and moons don’t have enough atmosphere to protect them against meteor and asteroid impacts. Earth’s moon, Mercury and even Mars are covered with round impact craters from these collisions.
What are Meteor Showers?
We see meteor showers, or shooting stars, when the Earth travels though clouds of particles left by asteroids (or, comets).
A meteor shower appears to originate from a single point in the sky, the “radiant”. Meteors seen near the radiant are approaching the observer and will appear as short streaks in the sky. However, meteors seen 45 to 135 degrees from the radiant are moving in a more parallel direction to the observer. These meteors will produce longer streaks in the sky.
Meteor showers are usually named for the constellation in which their radiant lies at the time of shower maximum. Thus, the Leonid meteor shower (peaking about November 18) will appear to radiate from the constellation Leo.
Since Earth’s orbit is virtually the same from year to year, the showers are predictable.
Here’s the complete Meteor Showers Calendar here for the dates of all the principal meteor showers during the year.
You’ll see the most meteors on a clear, dark night during a new Moon. If you live near a brightly lit city, drive away from the lights and toward the constellation from which the meteors will appear to radiate.
To see the most meteors, watch as late in the nighttime as you can, up till dawn. To view a shower, the meteor shower radiant must be above the horizon—most radiants are up by around midnight.
Grab and lawn chair and look up: Most meteor showers are very fast! They flash by in a second or less.
What is a Meteorite?
Every day, dozens of small meteorites fall to the Earth. Those that are seen coming down are called “falls.” Those that are recovered on the ground are called “finds.”
Meteorites are of great interest to researchers as studying them helps us to understand the formation and evolution of the solar system.
Meteorites can be recognized by their dark, often scalloped exterior. Usually they will be denser than a ‘normal’ rock and will often be attracted to a magnet. If recovered, it is best to place them in a clean plastic bag or wrap them in aluminum foil. Meteorites should also be handled as little as possible to help preserve their scientific value.
If individuals plan to search, they should always obtain permission of the land-owner before venturing onto private land!
Here’s how to find meteorites:
- Tape a strong magnet to the end of a broom handle. A meteorite contains a lot of iron, so it will stick to your magnet.
- If it’s an ordinary rock with lots of iron, it may stick too. You can tell a meteorite by its fusion crust, a thin, glassy coating that formed when the meteorite superheated during its fall through Earth’s atmosphere.
Fun Meteorite Facts
- The largest meteorite ever found in the United States weighed 15 tons and was found in 1902 in Willamette, Oregon.
- Since 1978, teams of scientists have collected over 15,000 meteorite specimens from Antarctica. They are easier to find on that continent’s snow-white surface.
- One of Canada’s most notable meteorites was found near Tagish Lake in northern British Columbia by Jim Brook on January 25, 2000. He almost mistook it for wolf poop.
Don’t worry. Most meteors are very small and the Earth is huge. Despite the current hype, and many rumors, there has been only one confirmed case of a meteor actually hitting anyone.
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