If you watch the night sky you might see what we often call “shooting stars” or “falling stars.”
These are meteorites that are various materials from our Solar System that create a bright streak of light as they near or enter Earth’s atmosphere.
It is very common to see quite a few meteorites each hour and during a special event called a “meteor shower” you might see as many as one hundred per hour.
How big are Meteorites
Many of the meteorites come from pieces of asteroids such as 4 Vesta, and most are small and are vaporized when they enter the atmosphere.
Some meteorites are much larger and can be sizes from a pebble to a boulder. These often make it through the atmosphere and do hit the ground.
Other meteorites come from other celestial bodies such as comets, our Moon, and even Mars.
When these metallic or rocky objects are traveling through space, they are called a meteoroid. The smallest ones that are around the size of a particle of dust are called micrometeroid or even “space dust.”
Once they travel through Earth’s atmosphere they can hit speeds of 10-70 km per second and they become heated by friction.
This is what gives them the glowing long streak of light that we see. Most meteoroids are slowed down by the atmospheric friction to around a few hundred km per hour.
If the object makes it through the atmosphere and does hit the Earth it is then called a meteorite.
Earth’s surface is 71% water so a majority of the meteorites land in the ocean. The rest that do hit land are often found by meteorite hunters.
Types of Meteorite
Meteorites are divided into many types based on what they are made of, the chemicals that are found inside of them, the specific type of chemical element known as “isotopic composition,” and the minerals that they contain known as mineralogy. Meteorites are also classified by specific type:
- Stony: a composition of rocky materials.
- Metallic: a composition of mostly iron.
- Mixture: a composition combining both iron and stony.
In addition to these three main types, there are other categories that are meteorite-specific.
One example is the pallasite meteorites that are classed as stony-iron made up of iron and nickel, but they also contain olivine crystals which are very common on Earth.
Meteorite hunters travel all over the world to find and collect them. Some are found in museums due to their incredible size while others are part of private collections.
Famous Meteorites
Meteorites are very valuable and are often bought and sold to collectors at various trade shows. Some of the most famous meteorites include:
- The Hoba Meteorite: weighing 60 tons and found where it hit in Namibia, Africa. It struck the Earth over 80,000 years ago but was discovered in 1920. It is the largest known meteorite on the planet and is made up of mostly iron and nickel, with a few other trace elements. This meteorite is a National Monument where thousands of people can see it each year.
- The Willamette Meteorite is 15.5 tons and 10 feet tall. It is the largest meteorite every found in the U.S. It is a pitted iron meteorite which is thought to be the remains of a planet with an iron core that was destroyed billions of years ago in a collision. While it landed over 1,000 years ago, it wasn’t discovered until 1902 by Westerners. It was long known by the Native American Clackamas tribe who called it Tomanowos and revered it as a source for healing.
- The Sylacauga/Hodges Meteorite: This was an unusual discovery in 1954 when a woman named Ann Hodges was taking a nap on her couch and an 8.5 lb meteorite crashed through her window and hit her on the hip. She only had a bruise, but her neighbors had watched the meteorite fall and described it as a “fireball shooting through the sky.”
- The Allende Meteorite was originally the size of a car but broke up into hundreds of pieces, crashing over Mexico in 1969. When the pieces were totaled up, they weighed several tons. This is the one meteorite that has been studied the most. It is a carbonaceous chondrite, thought to date back to the forming of the planets and Sun over 4.6 billion years ago. They are considered to be the most primitive objects in the Solar System and are made up of oxides, silicates, sulfides, water, organic compounds, and a few other types of minerals.
Q&A:
- What are the three types of meteorites?
stony, metallic, and mixture - What is the weight of the largest meteorite every discovered?
60 tons - When does a meteor become a meteorite?
when it hits the ground - What two nicknames do we have for meteors observed in the night sky?
shooting stars or falling stars - Where do most meteorites fall on Earth?
in the ocean - Where do scientists think meteorites come from?
asteroids and planets such as Earth, the Moon, and Mars