What is the difference between a meteor and a comet

Have you ever seen a fast moving streak of light in the sky? Some call it meteorite, some call it comet, some call it meteor and still some assume it's a rocket. Read this if you are really curious to know about amazing natural sight in our planet. 

Among all the interplanetary bodies visible to humans, stands out these two beautiful fast moving streaks of light, called meteors and comets.  But due to their physical similarities, humans sometimes can't tell their difference, and due to this, they sometimes mistake one for another. So in today's post, we are going to highlight the differences between a meteor and a comet, these will include what they are made up of,  how they are formed, and where they are formed in the outer space? But first, what is a meteor?

WHAT IS A METEOR?

In a layman's term, a meteor is a small particle of matter (usually a meteoroid) from outer space that finds it way in the earth's atmosphere. 

A meteor usually get ignited in the process due to the collision between itself and the atoms in the earths atmosphere that is why it always appear as an incandescent streak of light.

How are meteors formed?

When asteroids or other rocky space element collide (smash into each other) and shatter into smaller pieces, those debris are called METEOROID and they have not yet  find it place to the earth atmosphere. Some meteoroids are always forced out of their regular orbit and at high velocity due to the shock wave caused by the collision and it is still flying at high speed in the outer space. It is important to note that a meteoroid is not yet ignited because there is no presence of oxygen in the outer space, so it does not support  burning. 

As the smaller debris are moving randomly at different direction and with high speed, if any of it finds it way to the earth atmosphere, it will thereby exhibit different properties. What will happen is that the walls or outer shells of it atoms will collide with the outer shells of the atoms of the atmosphere, and thereby causes friction. So since there is the present of oxygen in the earth's atmosphere(you guess it right) it will ignite and cause that streak of light you normally see there burning. So because of these different properties, it is called a METEOR.

 Still, not all meteors usually find their way to the earth's surface, In fact 60% of meteors will completely burn off in the sky before reaching the earth surface. So some meteors that luckily survive a trip to the earth surface are termed as METEORITE. So we can see the aspect of science, how the same material can be given multiple names at different stages because of the properties they exhibit.

What are meteors made of?

Since meteors are from meteoroid, the question should be; what are meteoroids made of? but the aspect of chemistry has change the whole game during when a meteoroid enters the earth atmosphere.

Generally, meteoroids are made mainly of metallic element like nickel, Iron, Magnesium and even calcium. And also some non-metals like silicon and sodium. But as a meteoroid enters the earth's atmosphere, it molecules will break down into particles due to the high speed collision between itself and air and they will also recombine between themselves (both the molecules of air and that of the meteoroid). In that process, some other element such as nitrogen, oxygen and other rare atmospheric gases will be emitted.

The colors of the meteors also has something to say about their chemical composition (reference the image above).  The speed at which the meteor enters the Earth’s atmosphere can also affect the colors they exhibit. The faster a meteor moves, the more intense the color may appear, according to the American Meteorological Society (AMS). Meteoroids are formed in a region further closer to the sun.

WHAT ARE COMETS?

Comets are frozen and icy galactic bodies which when orbiting close to the sun, vaporizes and begin releasing gases and dust into it surrounding in a process called outgassing. Comet have a icy center called "the neucleus" or core and it surrounded by a large cloud of gases and dust called the COMA. 

The process of outgassing is due to the icy core getting warm as a result of receiving solar radiation and then it vapourizes and produces the surrounding coma. The preence of the coma which is very observable is what distinguishes the comet from other celestial moving object, like the asteroid and meteoroids. 

What are comets made up of?

Comets are divided into 2 major parts, which are the Neucleus(or core) and the coma and each of them are composed of different states of matter.

1. The Neucleus : This is the center or core of the comet. They are composed of mainly ice, rocks and frozen gases such as carbon dioxide, methane and ammonia.
2. The Coma : When the neucleus is expose to solar radiation and solar wind, it get warm and then spew into a large stream of dust and gases forming a cloud like  atmosphere around the neucleus called COMA. So water and much more gaseous compounds and element accommodate the coma.  

The pressure exerted by the solar radiation on the comet causes it to streamline and form a long pointed tail, divided into the gas tail and dust tail.

It is also important to note here that unlike the meteor, the comet is not self illuminated, both the core and the coma are illuminated by the sun. Like are earths satelite (the moon), the comet is illuminated by reflection and only becomes more visible to humans in the night.

Meteors	Comets
Mainly made up of rocks and metals	Mainly made up of ice and dust
Existed from debris of asteroids and other planet	Existed billions of years ago when the solar system was formed
Formed closer to the sun	Formed further away from the sun
Smaller in size	Very large in size
Are self illuminated	Are not self illuminated, they depend on reflection from the sun