Key difference: An asteroid is a large chunk of rock that orbits around the sun. Asteroids are also known as planetoids or minor planets. A meteor, on the other hand, refers to the flash of light that follows an interplanetary debris as it enters our atmosphere. Meteor is not the debris itself, but the flash of light caused by the debris. We often refer to meteor as a falling star or shooting star.

Both asteroids and meteorites are objects in space. An asteroid is a large chunk of rock that orbits around the sun. Hence, asteroids are effectively part of our Solar system. Asteroids are also known as planetoids or minor planets. The term minor planet is actually preferred in scientific communities.

Most asteroids are part of the asteroid belt located between the orbits of Mars and Jupiter. The asteroid belt consists of tens of thousands asteroids. They are generally rocks that have a high metallic content but no atmosphere. The size of an asteroid can range anywhere between a few meters wide and hundreds of km wide. They are smaller than planets but like planets some even have their own moons.

A meteor, on the other hand, refers to the flash of light that follows an interplanetary debris as it enters our atmosphere. Meteor is not the debris itself, but the flash of light caused by the debris. We often refer to meteor as a falling star or shooting star. The meteor, i.e. flash of light, is caused as the debris heats up due to the incandescence by the friction of the atmosphere. Many meteors appearing seconds or minutes apart, and appearing to originate from the same fixed point in the sky, are called a meteor shower.

Sometimes the falling debris is an asteroid that has been knocked off course and is pulled in by the earth’s gravitational pull. However, mostly the object is a meteoroid. A meteoroid is any debris in the Solar System. The size of a meteoroid can range from the size of a grain of sand to a boulder sized particle weighing 220 lbs (100 kgs). When these meteoroids enter the earth’s atmosphere they cause a meteor, i.e. a trail of light, which we refer to as a falling or shooting star. Usually, the meteoroid gets burned up in the process. If the meteoroid survives and lands on the surface of the Earth, or parts of it do, they are termed as meteorites.

Image Courtesy: arm.ac.uk, mikesastrophotos.com