Celestial bodies or heavenly bodies are objects in space such as the sun, moon, planets and stars. They form a part of the vast universe we live in and are usually very far from us. The glorious night sky is dotted with such objects and when we observe them using a telescope they reveal fascinating worlds of their own. Because they are so far away, we cannot see all of them using the naked eye but we need to rely on telescopes to study them.
Classification of Celestial Bodies
Stars are giant balls of hot gases that can produce their own light. Stars give out energy by converting Hydrogen gas into Helium in their cores. Stars are gigantic in size and have immense gravitational attraction. The sun is a medium sized star that gives us energy and makes life on earth possible.
Planets are large (almost) spherical objects that revolve around the sun. Planets move in fixed orbits around the sun. There are 8 planets in our solar system. Planets may be made of rocks, metals, gases like hydrogen, nitrogen and methane. The earth is also a planet and is the only place in the universe that we know that supports life. Planets that revolve around other stars are called exoplanets.
Satellites are objects that revolve around planets. They form the essential part of the celestial bodies. These may be of natural origin or sent by humans. The moon is a natural satellite of the earth and revolves around it because it is bound by the Earth’s gravitational pull. Man also has placed artificial or man-made satellites around the earth and other planets to study them and for communication purposes.
These are small chunks of ice and rock that come from the outer edge of the solar system and come close to the sun. When they approach the sun, the ice on them vaporizes creating a beautiful tail behind them.
These are small irregularly shaped rocks made up of metal or minerals that orbit the sun. Most of them are found between Mars and Jupiter in an area known as the asteroid belt.
Meteors and meteorites
These are objects from space that enter our atmosphere as they are pulled by the earth’s gravity. Meteors are usually are small and burn up in the atmosphere as they enter the earth. This creates streaks in the sky as though a star has fallen. They are commonly called shooting stars. If a meteor is large enough it can reach the ground and create a crater. Such objects are called meteorites.
Galaxies are large groups of stars held together by gravity. The sun and the solar system is part of a galaxy known as the Milky Way. Other galaxies are usually so far away that they look like stars in the night sky. The Andromeda galaxy and the Large Megallanic Cloud are galaxies that can be seen with the naked eye on a clear night.
The next time you go out to wonder at the night sky, try to identify these objects. If you can get a star chart, use it to find the different celestial objects mentioned in the night sky.
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