Important Definitions For Univers

Our Universe

The 'Universe' means everything that exists around us. Our earth, planets, stars, moons etc. are parts of the universe. The universe began with a tremendous explosion called the 'Big Bang' about 15,000 million years ago.

1. Galaxy

An enormous group of millions of stars.

2. Comet

A ball of dust and gases that orbits around the sun in an oval shaped path and has a tail pointing away from the sun.

3. Crater

A hole made when a lump of rock from space hits a planet or a moon.

4. Meteorites

The large chunks of rocks that reach the Earth's surface without burning up.

5. Meteoroids

Chunks of rock or metal flying through space. These are much smaller than asteroid.

6. Meteor

A streak of light in the sky, caused when tiny rocks burn up in the earth's atmosphere and filter down to earth and dust.

7. Asteroids

Tiny planet like rocky bodies that orbit around the sun.

8. Atmosphere

The layer of gases around a heavenly body.

9. Constellations

The patterns that bright stars make in the night sky and which never change.

10. Moon

A body that orbits around a planet, also called a satellite.

11. Nebula

A cloud of dust and gas in space.

12. Space

Another word for Universe.

13. Eclipse

It happens when one heavenly body passes in front of another and blots out its light.

14. Milky Way

The faint band of light arching across the sky that we often see on dark nights. It contains millions and millions of stars.

15. Observatory

A place where astronomers study stars.

16. Light year

The distance light travels in one year about 95 lakh million kilometres or about 3 lakh kilometres per second.

17. Interstellar space

Space outside the solar system and among the stars.

18. Pole star or Polaris

It is a star almost direct above the earth's North pole and does not appear to move.

19. Supernova

A star that flares up brilliantly as it blows itself up.