Here we are discussing some common points of “universe”, which are mostly important for SSC, PSC, WBCS, RAIL, TET, CTET and many other examinations.
What is Universe ? – The Universe is all things that we can can touch, feel, measure and detect. It includes all living and non living matters. It also includes billions of galaxies .
Some Important Points about Universe :
- The Universe is a vast expanse of space consisting of all heavenly bodies like galaxies, stars, planets, satellites etc.
- Astronomy is the branch of science which deals with the study of the heavenly bodies.
- Light year is the distance traveled by light in air in one year.
- The nearest star from the earth other than Sun is Alpha Centauri.
- The solar system consist of the Sun, its eight planets and other heavenly bodies like asteroids, meteors, meteorites and comets etc.
- The motion of planets is governed by Kepler’s Law of motion.
- Comets appear after regular interval of time and are consider as time keepers. Halley’s comet appears after every 76 years.
- A galaxy is the building block of the Universe. A galaxy consists of every large group of stars and their families, dust and gases held together by attractive gravitational force. Each galaxy contains 100 billions stars. Our galaxy is milky way galaxy or Akash Ganga.
- Pole star or Dhruva Tara appears stationary to the people on the earth pole star defines the north direction. Pole star lies above the earth’s north pole i.e on the axis of rotation of the earth.
- Constellation – A group of stars which forma certain shape or pattern is known as constellation. Astronomers have recognised 88 constellations.
- Satellite – A small body revolving around a planet in an orbit is known as a satellite. They are two types (i) Natural satellite – Just like Moon. (ii) Artificial satellite – Man made satellite . India sent the first artificial satellite named Aryabhatta on 19th April 1975.
- Communication Satellite – It is a geo stationary satellite. it plays an important role in communication technology.
- Remote Sensing Satellite – It is not for communica.tion purpose. Remote sensing means collecting information from distance.
- Indian space research programme has two object (i) to develop space technology for mass communication and education and (ii) to develop space technology for survey and management of the natural resource.