Have you ever made a wish on a falling star? Did you wish for a helpful Kids in the Biosphere blog post about what falling stars really are? I hope so! Let’s meet the meteoroids, meteors, and meteorites… otherwise known as shooting or falling stars! And at the end of the blog you’ll find out how to see an amazing meteor shower in the next week or so!
What's the Difference?
A meteoroid is a chunk of rock in outer space. It can be tiny like a grain of sand or big like a house. Anything much larger is usually called either an asteroid or a comet (bigger space rocks). Nearly all meteoroids form when they break off comets or asteroids. Bits and pieces break off when big space rocks pass by the sun, which is of course very, very hot. These big space rocks leave a bunch of little meteoroids in their paths… almost like footprints! As the Earth orbits around the sun, it sometimes passes through a path of a space rock. When this happens, the Earth encounters lots of meteoroids which are sometimes visible to us.
|Figure modified from Chaisson & McMillon: A Beginner's Guide to the Universe|
If a meteoroid gets really close to the Earth, it might enter the Earth’s atmosphere (the sky). Remember that there is no atmosphere in outer space. This means the “sky” in space has none of the gases that make up what we call “air”. With no air, humans can’t breathe in space! This is why astronauts must wear special space suits that have a long tube to pump air from a spacecraft into the astronaut’s suit.
When a meteoroid enters the Earth’s atmosphere it is called a meteor. The meteor encounters all the gases we have around the Earth, and the friction that builds up creates a lot of heat (see box 1 – rubbing hands to create heat). All this heat makes the meteor burn up and glow. This is what we see when we see a “falling star”. In general, the bigger the meteoroid, the brighter and longer-lasting the meteor.
If a meteor is pretty big it might not fully burn up, and it might make it all the way down to the Earth’s surface. We now call it a meteoroid. Most meteoroids are tiny like pebbles because large meteors break apart as they burn up and fall to the Earth. More than 40,000 meteoroids have been found on Earth! Usually scientists look for meteorites out in deserts because it is much easier to see a rock when the only other thing on the ground is sand or ice!
|Scientists in Antarctica study a meteorite. Credit: NASA|
So, are you excited about meteor showers yet? I hope so, because right now Earth is passing through the path of a big space rock called the Swift-Tuttle Comet, meaning you have a chance to witness a meteor shower! This meteor shower is called the Perseids (“per-say-ids”) because you can see lots of meteors near the constellation called Perseus. And the peak of this year’s Perseids meteor shower is August 11th and 12th! Check out the METEOR WATCHING activity below!
ACTIVITY: Watch a Meteor Shower!
The Perseids are a great meteor shower to watch because they peak in August, when nights aren't too chilly here in the Biosphere! The Perseids are active from July 17 to August 24, but the best days are August 11th and 12th. During this "peak", the Earth passes through the middle of the Swift-Tuttle comet's path, so you have the best chances for seeing awesome meteors! You might see around 40 meteors per hour! Follow these tips below to watch a meteor shower show!
- Make a list in your Nature Notebooks of different wishes you'd like to make when you see a meteor (even if it's not actually a falling star, it's still fair to wish on one!).
- Pick a clear, cloudless night for meteor-watching! Did you know that meteors still happen during the day? It's just that it's hard to see them. This is why we watch for meteors at night.
- Dress warmly -- it can get chilly at night! Remember to bring blankets and maybe a hot drink (hot chocolate, anyone?).
- Find a place away from lights. This will make it easier to see fainter meteors. Perhaps you can find a nice spot by the shore of a lake or Georgian Bay, away from the lights of towns and cottages.
- Find a place where you have a wide open view of the night sky. Now you have a better chance of seeing meteors all across the night sky.
- Lay back on a recliner chair or lay on flat ground (this is where a pillow and blanket come in handy!). You'll get a much better view of the whole sky this way.
- Try to go out when the moon is low in the sky. The moon adds brightness and makes it harder to see meteors. This year during the Perseids, the moon will be rising around midnight. See if you can watch for meteors after dusk but before the moon rises, as the sky will be a little darker.
- Be patient! It can take your eyes several minutes to adjust to the dark. Soon you should be able to see thousands of stars... and hopefully some meteors!