Comets, asteroids, fireballs difference between them

 

   The most of the celestial bodies that enter frequently in  our earth's atmosphere are meteors, asteroids, fireballs, etc... These bodies may or may not cause impact on the surface , the scientists only predict whether it may cause catastrophe or not.

Space rocks:

1. Meteoroid:

               When the space rock is  rest in the outer space is called meteoroid. A meteoroid is a small rocky or metallic body in outer space. Meteoroids are significantly smaller than asteroids, and range in size from small grains to one-meter-wide objects. Objects smaller than this are classified as micro meteoroids or space dust.

2. Meteor:

                It is the space objects i.e. meteoroid which enters into planets or moons atmosphere and get fired up due to friction by atmospheric interaction, which causes the dust particles present on the surface to burn up and started to disintegrate the celestial body into pieces . The fireballs or “shooting stars” are called meteors. It mostly consists of dust, clay, silicate materials and most of the metallic substances.

                        

3. Meteor shower:

                            Almost all the material is vaporized in Earth's atmosphere, leaving a bright trail fondly called "shooting stars." Several meteors per hour can usually be seen on any given night. Sometimes the number increases dramatically—these events are termed meteor showers.

      4. Meteorite:

                    The fired up meteor in the upper atmosphere may or may not reach the surface. If the meteor reaches the surface of the planet or moon the left over rocks/debris on the surface is called as meteorites. Mostly the meteorites are made up of metallic elements,  because they only not be easily disintegrate by the atmospheric friction.

5. Asteroid:

                Asteroids are the large space rocks that are many more similar to planets / moons. They are also called as planetoids or minor planets.  The size ranges from 1 meters to few kms. Asteroids are the one which revolve around the sun at a particular orbit by interfering with the planets orbit. Most of the asteroids are from the asteroid belt between mars and jupiter.  Asteroids may also come from outside the solar system.The mass of all the asteroids discovered yet  is less than that of the mass of moon.

6. Fireballs:

            A fireball is an unusually bright meteor that reaches a visual magnitude of -3 or brighter when seen at the observer’s zenith. Objects causing fireball events can exceed one meter in size. Fireballs that explode in the atmosphere are technically referred to as bolides although the terms fireballs and bolides are often used interchangeably.

Fireball of perseid shower as seen from space station