A Planetarium is a domed building where the movements of Sun, Moon, Stars, Planets, Constellations, etc are projected for public education and entertainment. It is made up with a dumb bell shaped planetarium projector, which recreates the mighty sky on the dome-shaped ceiling. One can experience the ecstasy of looking at the starry sky in a planetarium and learn a lot about the universe.
Great scientist Archimedes of ancient Rome, who gave the ‘laws of floating’, is credited with the discovery of the first Planetarium. The earliest reference to a model of the Sun, Moon and Planets is mentioned in Cicero’s book ‘De Republica’ written most probably in 60 BC. The concept of a Planetarium with a sky projector projecting stars on inside of dome in a realistic way is of recent origin. The credit for designing the modern type of Planetarium with a movable projector goes to Carl Zeiss of Jena (Germany). The idea of projecting the stars on a fixed dome using the Planetarium projector goes to Walther Bauersfeld of Germany. The first Zeiss planetarium was fabricated in 1923 in Germany based on this idea.
Planetarium is a very complicated instrument with lenses, prisms and mirrors. It not only can show the stars almost precisely as they are in the real sky, but also can show their movements from season or as they seem from various places. It can also replicate the movements of the sun, moon, planets and other heavenly bodies in the sky. The Planetarium sky projector brings the night sky of the past, present and future in a realistic way. Now-a-days modern planetarium with slide projectors can stimulate events such as space travel and landing on other planets.
Planetariums are very useful because it is very difficult to know about the heavenly bodies just by looking at the sky. Again, it is a very time consuming process to track the heavenly bodies because of pollution, clouds etc. That is why in a Planetarium the movements of heavenly bodies occurring through out a year can be seen in an interval of few seconds. Planetarium programmes can explain about the earth and its weather, origin of life, space travel and so many things. The Planetarium also aims at teaching all about the mysteries of the universe. Hence, it is employed to educate not only astronomers and navigators but also to all. For students, visiting the planetarium is most essential as it provides them special knowledge about the universe.
The first major Planetarium in India- the Birla Planetarium was set up in Kolkata in 1962. Now there are so many Planetariums in India. The biggest and most modern Planetariums are the Birla Planetarium of Kolkata and Nehru Planetarium of Mumbai. In our state Orissa, there is the Pathani Samanta Planetarium at Bhubaneswar, which is named after Samanta Chandrasekhar, a great astronomer of Orissa.