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A Dummy’s Guide to Meteors and Meteor Showers
Comets are much different from meteors, as they’re huge balls of ice. Photo Credit: NASA

Characteristics of Icy Comets

Comets look like dirty snowballs, as they are comprised of dust, rocks, and frozen gas. As these comets get closer to the sun and experience its heat, the ice on their surface regions will start to melt. This helps in forming a gas cloud, which is then stretched out by solar winds to create the famous tail of a comet. Shorter-period comets will be the remnants from the formation of the solar system, which took place at least 4.6 billion years ago.

They mainly originated from the icy objects belt beyond Neptune, where they got knocked into an orbit closer to the sun. These shorter-period comets have solar orbits, which are mostly less than 200 years old and seem to be entirely predictable. The longer-period comets might originate from a region, primarily termed as Oort Cloud. It lies around 100,000 times farther away from the sun than the Earth does. So their orbits might take as long as 30 million years, if not more.

A Dummy’s Guide to Meteors and Meteor Showers
Asteroids are much bigger than meteors and are known to do a lot of damage. Photo Credit: NASA/JPL

Rocky Meteors and Orbiting Asteroids

Primarily known as shooting stars, meteors are smaller rock pieces and debris that have entered the Earth’s atmosphere. They will strike the atmosphere at higher speeds, where friction will force them to burn. Most of the meteors are the size of a pea or even smaller than that, and will burn up completely before hitting the Earth’s surface. Occasionally, some of the more giant meteors will strike the surface and their remains will be called meteorites. NASA scientists have estimated that around 1000 to 10,000 tons of meteoritic materials get to enter the Earth’s atmosphere daily.

Sometimes referred to as minor planets, asteroids are larger rocky masses without atmospheres that move around the sun but are too small to be noted as planets. There are millions of such rocky masses in the central asteroid belt between Jupiter and Mars. Left after forming the solar system, these asteroids are created by combining various combinations of nickel, rock, clay, and iron. They might range in size from less than half a mile to around 600 miles in diameter. Over 150 of them have small moons. The gravity of Jupiter and occasionally from Mars, as well as interaction with other objects, can easily knock these asteroids out of the asteroid belt and place them in the path of the Earth.

A Dummy’s Guide to Meteors and Meteor Showers
As you can see, comets leave behind very large impact craters. It’s believed that a comet is responsible for wiping out the dinosaurs. Photo Credit: Pixabay

Comets and the Earth

There have been multiple theories about comets and their impact on Earth. Some have theorized that comets are a source of both the water on the planet and life’s building blocks. The largest meteorite ever found was located in southwest Africa and weighed around 120,000 pounds. Nearly 65 million years ago, there was an asteroid that produced a crater over 100 miles in diameter in the Yucatan Peninsula. This crater has been linked by multiple scientists to the extinction of dinosaurs.

In the United States, you have the Chesapeake Bay, which features a 56-mile wide crater, as created by an asteroid roughly 36 million years ago. According to NASA scientists, there are currently 1,238 known PHA or potentially hazardous asteroids in existence. These are asteroids that are larger than 500 feet that will most likely pass within 4.6 million miles of Earth.

A Dummy’s Guide to Meteors and Meteor Showers
Some meteorites are actually pretty small, but they all have a glossy surface. Photo Credit: Flickr

Identifying Meteorites

Meteorites happen to be the rarest pieces of rock found on planet Earth. Many pieces of stone are tested each year by people who believe that they have come across a meteorite. Among the thousands, one or maybe two might be an actual rock from space. Some essential characteristics can help you recognize a meteorite. You can try to determine whether or not a rock is from a meteorite through some home tests. Home testing can save you money on your quest to test found rocks. Using a home testing kit can be a life-changing opportunity for many people.

These home tests are pretty simple and tend to produce accurate results most of the time. The purpose of home testing kits is to help people understand and know if the rock they have found is genuinely from space or another example of terrestrial rock known scientifically as meteor wrongs. Some pictures available on the internet may be useful and can help differentiate meteors from other simple rocks as well.

A Dummy’s Guide to Meteors and Meteor Showers
The fusion crust is why meteors have a specific surface appearance from all the heat. Photo Credit: Wikipedia

Fusion Crust and its Characteristics

All meteorites will fall across the atmosphere at a higher velocity, which will force the outer part of the material to burn off. This melting will end up with one smooth outer coat, commonly referred to as a fusion crust. This crust is mainly a darker gray or even charcoal black color. The black fusion crust seems to be of two different textures: one is a shiny texture and another one is a dull velvety texture. The fusion crust comprises straight and flowing lines while moving molten rocks across the Earth’s surface. This is pretty common for the meteorites to have fused their outer body with some chips. With time, weathering takes place, leaving very little of the fusion crust on top.

Be sure to become familiar with the shapes of meteorites as well to determine if you have one in your possession. Meteorites are not smooth, round-shaped balls and are mostly known for their irregular shapes. Primarily, these space rocks are angular with rounded-off corners. Some will even show marks or pits on the surface that are called thumbprints. Scientists call these marks regmaglypts and these are formed as blistering air starts to destroy the rock when it moves through the Earth’s atmosphere.

Most of the time, people might come across some rusty iron mass and get confused by thinking they have found meteorites. Some sources of such meteor wrongs are mill balls or cannonballs. These old, rusty objects are known to have an iron-like meteorite appearance. It is only through chemical tests that you can determine if those are human-made or not. Iron, as found in meteorites, can be termed as a perfect mix of a nickel alloy. So, if the chosen rock fails to show any sign of nickel, then it cannot be an iron meteorite.

A Dummy’s Guide to Meteors and Meteor Showers
Meteors that are a red color are filled with iron. Photo Credit: Wikimedia Commons

Stable Nature and its Colors

Slag from industries manufacturing steel and iron will have some metallic particles within. Slag is a material that often gets confused with meteorites. However, slag will come out to be porous in nature or bubbly sometimes, which proves that you cannot call it a meteorite. In some instances, meteorites might exhibit some cavities, but those can never be porous or even bubbly to look at. To say the least, meteorites are solid rocks and could have some pits on the surface region, but the inside will be completely dense. Basalts, volcanic stones, and lavas can always be porous and can get mistaken for these space rocks.

You can determine if you possess a meteorite or a simple earth rock through its colors, as well. Fresh meteors are mostly black and the fusion crusts will show some flowing marks and some details to help them be identified. After staying on the ground for too long, they will start changing color and the fusion crusts will wear off. Then the details on their bodies will disappear completely. However, iron, as presented in meteorites, will rust because of the weather. When the iron-based metal starts to rust, it will stain the inside of the rock-based body and even the exterior. Those spots which started as an orange or reddish hue on black infused crust will turn into a rusty brown color with passing time. You can see the crust sometimes, but it won’t be black.

A Dummy’s Guide to Meteors and Meteor Showers
Meteorites can range from pebbles the size of a pea to a golf ball to even bigger. Photo Credit: Wikimedia Commons

Keep Learning About Meteors and Meteorites

It is exciting to learn about meteors and meteor showers, but only from accurate sources. Keeping a close watch on scientific discoveries from reliable sources like NASA will help you get the right information. It is stunning to see a shooting star, but once you start to understand its significance, you will fall deeply in love with it. With help from this article, you can try to differentiate meteorites from the simple rock formations found on Earth.