Asteroids, Comets, and Meteors: A Guide to Space Rocks in the Night Sky
A piece of the Campo del Cielo meteorite. (image credit: Carlos Zito)
Post Author - Peter Bashaw
Across the solar system, there are trillions of pieces of rocky debris leftover from the formation of the sun and our planets. These space rocks have many different names that are mistakenly used interchangeably, so if you’ve ever wondered what’s a meteoroid and what’s a meteorite, or the difference between an asteroid and a comet, we'll clue you in!
Asteroids are rocky objects that make up the asteroid belt between the four inner terrestrial planets and the four outer gas giants. The difference between an asteroid and a meteoroid is a question of size, with anything smaller than one meter in diameter being a meteoroid. Asteroids on the other hand can be very large, with the largest being the dwarf planet Ceres with a diameter of 940 kilometers.
When a meteoroid falls to Earth, friction from the atmosphere produces light and heat. This is what we call a meteor. Seen at night, we might call this a shooting star, or if it’s particularly intense a fireball. Air resistance usually breaks up meteoroids as they fall, scattering their pieces across a strewn field. The material that makes it to the Earth’s surface is called a meteorite.
Comets are an entirely different kettle of fish. These space rocks have a core of material from the solar system’s formation and are surrounded by a layer of dust and ice. Unlike asteroids, they follow their own orbits around the sun. If gravitational forces draw them to the sun, the ice begins to vaporize and leak through the comet’s crust in jets. This produces a cloud of dust and ice around the comet called a coma, as well as a tail of material that can stretch across millions of kilometers.
Looking for some hands-on experience with space rocks? Lucky for you we have plenty in our Meteorite Collection...
Read More
Featured Product
Al Capone HQ - Lexington Hotel Brick
Latest News
-
Jul 04, 2025 Viking for a Day: Researchers Recreate Viking Voyages! Read More -
Jun 30, 2025 When the Sky Split in Two: The Tunguska Event Read More -
Jun 27, 2025 The Vera C. Rubin Observatory Releases its First Photos! Read More -
Jun 19, 2025 Snakestones, Shaligrams, Ammonites, Oh My! All About Ammonites Read More -
Jun 11, 2025 The Artist Behind the Macintosh: Susan Kare and Apple Computers Read More -
May 30, 2025 Learn how Scientists Used Zircon Crystals to Date a Meteorite Impact! Read More
Cool Things!
Viking for a Day: Researchers Recreate Viking Voyages!
For one student at Lund University in Sweden, reading studies and collecting archaeological evidence wasn’t enough to grasp the full picture of an awe-inspiring people of the Nordic region: The Vikings. In a new study, a team of researchers set out to learn more about these nomads of legend by setting off on their own voyage of the seas, complete with historically accurate ships!
The Vera C. Rubin Observatory Releases its First Photos!
The dazzling images in this article are some of the first to be released by scientists using equipment at the Vera C. Rubin Observatory in the Elqui Province of Chile. However, these images represent just the tip of the iceberg for the new facility.
Snakestones, Shaligrams, Ammonites, Oh My! All About Ammonites
Ammonites, the aquatic ancestor of cephalopods such as the octopus and nautilus, have captured our imaginations for centuries. Their spiraling fossilized shells have been known by many names throughout history. Here is our roundup of the most fascinating ammonite folklore!
Specimen Deep Dives
When the Sky Split in Two: The Tunguska Event
Returning to the Moon: The Apollo 14 Mission
The Secrets of the Space Shuttle: Learn about Mini Museum's Shuttle Tile Material!
Long Form Articles
The Artist Behind the Macintosh: Susan Kare and Apple Computers
While the two Steves, Jobs and Wozniak, are the most well known faces behind Apple computers, equally important to the products and culture of the company were those who crafted the experience of using their computers through design. The most notable of these visual architects was Susan Kare, a designer responsible for “humanizing” Macintosh computers.
Can I Lick It? Yes You Can!
Have you ever been unable to tell if a fossil was really a fossil, but you were too embarrassed to admit it? Have you ever wanted to lick a fossil just because, but you didn’t want to risk judgment from your peers? Well, good news! You can kill two birds with one stone! Licking a fossil can actually help you determine if it’s the real deal or just another rock.
Is It Legal To Own a Meteorite: How to Start Your Outer Space Collection!
Meteorites are some of the rarest geological specimens to be found on Earth. Of course, since these stones are not of our world, purchasing them can sometimes be a confusing process. Is it legal to own a meteorite? In short, yes! Read on for help starting your cosmic collection!