A meteor, also known as a shooting star, the path of meteor is visible and glowing meteoroids glowing meteoroid, comet or asteroid through Earth's atmosphere, after being heated to burning by collisions with air molecules in the upper atmosphere, making a streak of light via its quick motion and sometimes also by flaking glowing material in it. Although a meteor may seem like few thousand feet from the Earth meteors naturally occur in the mesosphere at altitudes from 76 to 100 km (250,000 to 330,000 ft). The root word meteor comes from the Greek meteōros, that says 'tall in the air'.Billions of meteors enter Earth's atmosphere daily. Most meteoroids that cause meteors are about the size of a particle of sand, i.e. they are usually millimeter-sized or even smaller. Meteoroid sizes can be measured from their mass and density which, in turn, can be expected from the observed meteor trajectory in the higher atmosphere Meteors showers is a natural phenomenon and it can occur in showers, which begins when Earth travell through a tributary of debris left by a comet, or as 'random' or meteors, not associated with a specific stream of space debris. Several specific meteors have been seen, largely by members of the public and other largely by accident, but with enough information that orbits of the meteoroids producing the meteors have been measured. The atmospheric speeds of meteors result from the movement of Earth around the Sun at about 30 km/s (68,000 mph), the orbital speeds of meteoroids, and the gravity well of Earth.