Introduction A meteor is a term used to describe the streak of light that appears in the sky when a meteoroid enters the Earth’s atmosphere and burns up due to friction with the air. This phenomenon is commonly referred to as a “shooting star” or “falling star.”

Definition and Description

1. Meteoroid:

   • Definition: A meteoroid is a small rocky or metallic body in outer space. It can be as small as a grain of dust or as large as a boulder.
   • Origin: Meteoroids are often fragments of asteroids or comets. They can be remnants of cosmic debris left behind from the formation of the solar system.

2. Meteor:

   • Definition: When a meteoroid enters the Earth’s atmosphere, it encounters friction with the air, which heats it up and causes it to glow. This glowing trail is what is observed as a meteor.
   • Appearance: The meteor appears as a bright streak of light across the sky, and the brightness is due to the intense heat generated by the meteoroid’s rapid compression and friction as it travels through the atmosphere.

3. Meteorite:

   • Definition: If a meteoroid survives its fiery passage through the atmosphere and lands on the Earth’s surface, the surviving fragment is called a meteorite.
   • Types: Meteorites are classified into three main types: stony, iron, and stony-iron meteorites, depending on their composition.

Process of a Meteor

1. Entry into the Atmosphere:

   • As a meteoroid enters the Earth’s atmosphere, it travels at extremely high speeds, typically between 11 km/s to 72 km/s (25,000 to 160,000 mph).

2. Friction and Heating:

   • The friction between the meteoroid and atmospheric particles generates intense heat, causing the meteoroid to heat up and eventually incandesce. This produces the bright streak of light known as a meteor.

3. Burnout:

   • Most meteoroids disintegrate and burn up completely before reaching the Earth’s surface. The point where the meteor appears to “burn out” or vanish is known as the terminal burst.

4. Meteor Shower:

   • Occasionally, when Earth passes through a stream of debris from a comet, multiple meteoroids enter the atmosphere simultaneously, resulting in a meteor shower. During a meteor shower, numerous meteors can be observed in a short period.

Recent Examples and Observations

1. Perseid Meteor Shower:

   • One of the most well-known meteor showers, the Perseids, occurs annually around mid-August. This meteor shower is caused by Earth passing through the debris left by the comet Swift-Tuttle.

2. Chelyabinsk Meteor:

   • In February 2013, a meteor exploded in the atmosphere over Chelyabinsk, Russia, causing a significant shockwave and damage. This event highlighted the potential hazards of meteoroids and the importance of monitoring near-Earth objects.

3. Tunguska Event:

   • In 1908, an explosion caused by the airburst of a meteoroid or comet over Tunguska, Siberia, flattened an estimated 2,000 square kilometers of forest. This event remains one of the most significant meteor-related incidents in modern history.

Conclusion

A meteor is the visible streak of light produced when a meteoroid burns up upon entering the Earth’s atmosphere. While most meteoroids disintegrate before reaching the ground, their study provides valuable insights into the composition of our solar system and the potential risks associated with near-Earth objects.