Difference between Meteors, Asteroids, Comets, and Shooting Stars

Posted on Jul 7, 2020


Meteor observing is a fun hobby (albeit quite demanding) that often leads to expansion of interests. For instance, many astronomers start watching meteor showers and slowly expand the scope of their interest. They often end up researching other celestial bodies and phenomena, and all details that come with them.

To become a proper observer of meteor showers, one needs to know elementary things like meteors, meteorites, and meteoroids. We already covered this topic, but it cannot hurt to get a refresher.

In this article, we will cover the definitions and show you how to differentiate meteors from comets and asteroids. Let’s get right to it!

Shooting Stars Don’t Exist – They Are Meteors.

The first thing that we must clarify is that shooting stars do not exist. Stars cannot fall from the sky – they can only fall apart (explode) and their remnants later float in space. However, the phenomenon which we call a ‘shooting star’ is a meteor. Meteors are the light phenomena that occur when a meteoroid from outer space crashes into Earth’s atmosphere. On its way to the ground it vaporizes (oxygen in the air causes it to ablate) and it lights up. The chemical composition of each meteoroid depends on the parent body, but we’ll come to that. The only thing that we need to make clear is that ‘shooting stars’ are not real – those are just meteors that have entered our atmosphere.

Meteors Come from Asteroids (Sometimes)

Asteroids are massive extraterrestrial bodies. Scientists often describe them as mini planets – precisely because of their size. They usually orbit close to the Sun. When a chunk detaches from the asteroid – it’s called a meteoroid – it continues floating in space in its trajectory. Should it crash into Earth’s atmosphere, it will burn up thus becoming a meteor.

Hence, meteors are light phenomena that follow the rocky body from outer space. That celestial body that’s made up of rock typically comes from an asteroid. So, the short answer about the differences between meteors and asteroids is that meteors (sometimes) originate from asteroids.

Asteroids and Comets – It’s All About What’s Inside

Among the four terms that we have here, asteroids and comets are the easiest to mix up. Amateurs and novices often miss the subtle differences between the two celestial objects because they share a lot of similarities. Objects that have mixed characteristics only add to the confusion between the two types of bodies.

However, once you dive deeper into the subject, you can quickly realize that the differences are not subtle at all. But how so?

The first difference is the chemical composition. Asteroids consist of rock and metals, whereas comets consist of ice, dust, and rocky materials. Although both formed at approximately the same time, the location is the key to their differing composition.

Asteroids orbit around the Sun, which is where they formed. On the other hand, comets are not close to the Sun – hence all the ice. Whenever a comet approaches the Sun, it vaporizes (and thick layers of ice disappear).

Next, comets typically have tails, which is rare with asteroids.

Finally, comets are usually single objects that fly solo (no pun intended). Asteroids, on the other hand, have shorter orbits and are mostly in groups.

Conclusion

We hope this wasn’t too confusing! Astronomy is an exceptional science, but there are many things to remember and learn. Though, what we discussed above only scratches the surface.

Nevertheless, we know how the surface is important, especially with meteors!

Now, let’s sum everything up!

Asteroids are massive extraterrestrial bodies that are made up of metal and solid materials. They have solid surfaces and orbit closer to the Sun.

On the other hand, comets have thick layers of ice and dust, and they are farther from the Sun.

Both objects can fall apart and lose chunks. When this happens, the detached pieces float in space. If they encounter Earth, they crash into the atmosphere and start burning.

The burning process is seen only as faint light in the sky – and that’s code for meteors.

Finally, in the beginning, we did not have extensive knowledge of astronomy. So, we thought that these bright meteors were stars that were falling from the sky. And when a star is falling from the sky, it’s called a ‘shooting star’. But that is just a different name for a meteor.