A planetarium is a theatre built primarily for presenting educational and entertaining shows about astronomy and the night sky, or for training in celestial navigation. It is one of the most efficient tools in simulating all of the universe. The term planetarium was originally used to describe a type of mechanical model designed to portray the orbital motions of the planets and their moons.
The planetarium profession started just 50 years ago. At that time progress in optics, instrumentation, and electricity made possible the realization of a two-thousand-year-old idea; the perfect representation of the starry sky inside a room. With it came the possibility to have a celestial time machine, with time marked by the motions of the planets.
Twenty centuries ago, maps of the sky were placed on the outside of globes to illustrate the heavens for the purposes of art and of learning. Archimedes is credited with the first device demonstrating planetary motions about 250 B.C. The next movement came with the enlargement of the globes. The most famous, the Gottorp globe constructed in the middle of the 17th century, was about 4 meters in diameter. The stars were holes in the globe.
With the coming of the Copernican idea and with advances in instrument-making, various models of the planetary systems were constructed as teaching devices. There are called “orreries” in English, but they are also known as planetaria. Generally considered as the first projection device for showing planetary motions is the Orbitoscope, invented about 1912 by prof. E. Hindemann in Basel.
In summer 1923, the first artificial starry sky started working in Jena. For over ten years, mechanics, engineers, astronomers, and physicists had worked on a device capable of projecting images of the fixed stars and planets onto a dome. Oskar von Miller, the founder and first Director General of the Deutsches Museum had commissioned the device from Zeiss in 1913. Miller wanted an installation for the Museum that would demonstrate the location and motions of the fixed stars and planets, the Sun and the Moon.
The heart of the planetarium is the projector, a sophisticated precise mechanical-optical device that produces a realistic image of the starry night. The world’s first planetarium projector was designed and built at Zeiss between March 1919 and July 1923. After a brief public demonstration in Munich and Jena, the first projection planetarium worldwide was installed at the Deutsches Museum on May 7, 1925. More than 8.3 million visitors have attended more than 90.000 demonstrations since then until 2007.
Planetarium, a theatre devoted to popular education and entertainment in astronomy and related fields, especially space science, and traditionally constructed with a hemispheric domed ceiling that is used as a screen onto which images of stars, planets and other celestial objects are projected. The term planetarium may also refer to an institution in which such a theatre functions as the principal teaching arrangement or to the specialized projector employed. The planetarium is applied in yet another sense to describe computer software or Internet sites that allow the user to simulate views of the night sky and various celestial phenomena.
Permanent planetarium installations vary greatly. Those within a large supporting institution may coexist with extensive exhibit space and museum collections and have sizable professional and support staffs. Their projection theatres can be 25 meters (82 feet) or more in diameter and have capacities in excess of 600 persons. On the other hand, community or local college planetariums may accommodate only small groups of people. In a separate class are portable planetariums comprising inflatable domes and lightweight project that can be set up at schools and can hold several dozen students at a time.
In a typical planetarium theatre, programs-commonly called sky shows- are offered to the public on a regular schedule. Show themes may focus on straightforward astronomical and space topics or take up related issues such as the cosmologies of ancient cultures, the extinction of the dinosaurs, or the future life on Earth. The trend, especially for large audiences and multiple daily shows, is toward total computer automation of the program, combining visual display, cued music and sound effects, and prerecorded narration. Large planetariums with technologically advanced multimedia installations often supplement their science programs with shows featuring pure entertainment based on light, video, and music.
Khayam planetarium in Neyshabur is the biggest planetarium in Iran with 30 meters diameter (28 meters for the screen show). It is located next to Omar Khayam tomb-the great Iranian poet, mathematician, and astronomer who developed the most precise calendar called Jalali. The planetarium complex is extended in a field near 8000 square feet.
Khayam planetarium has a hybrid simulation system; using one optomechanical and eight digital projectors manufactured by Zeiss Company it simulates the sky for 420 audiences and brings about the greatest indoor adventure ever.
Khayam planetarium offers different educational programs for all ages:
- Educational, astronomical and entertaining 3D and Fulldome shows
- Conferences and talks about astronomy in general