In the simplest terms, a planetarium can be defined as a theatre that is focused on the entertainment and popular education of astronomy and other related fields. Usually, it can be viewed as a hemispheric domed ceiling that is normally used as a screen on which the images of planets, stars, and several other celestial objects can be projected.
The term planetarium can also be used to refer to the institutions in which a theatre is primarily used for teaching. A specialized projector is also involved in this task. There are also several experts who refer to computer software and internet sites as planetariums. These sites and software must be able to simulate a view of the night sky or some celestial phenomena.
Types of Planetarium
One should remember that when it comes to permanent planetarium installations, then there are a lot of variances that exist in this domain. This means that planetariums that coexist with large supporting institutions often have an extensive exhibit space dedicated to museum collections. These types of planetariums also employ a lot of people in their professional and support staff.
Usually, the projection theatre of those kinds of planetariums can be 82 feet or 25 meters in diameter. The capacities of these planetariums can exceed over 600 people. On the other hand, when it comes to local college or community planetariums, those spaces are only able to accommodate small groups of people.
There is also a separate class of portable planetariums that consist of inflatable domes and lightweight projectors. The domes and projectors can be set up at school to hold several students at the same time.
It should also be noted that a projection instrument is vital for every great planetarium. That being said, the first modern electromechanical planetarium projector was built by Carl Zeiss, which was a German optical firm, in 1923. This projector was used in the Deutsches Museum in Munich.
The current versions of this instrument are more technically complex, controlled by computer combinations, uses motor drives, fibre optics, lenses, lamps, and other devices that help in designing the place of the planets, the sun, and the moon in their correct locations. Some devices also help in allocating the position of thousands of stars for hundreds and thousands of years.
There are also other instruments that can add several details like the Milky Way, horizon scenes, comets, nebulae, meteors, reference lines, and scales. These features can be used for celestial navigation and descriptive astronomy.
Institutional Planetariums
These days planetariums that are based out of institutions are replacing and complementing electromechanical projectors with other technologies. This includes all-digital projector systems that are equipped with fish-eye lenses. These planetariums also come with laser projection systems that can scan the image on the screen by using colour-controlled laser beams.
A seamless blending of images of the sky, artwork, videos, photos, and animations generated by the computer can also be accomplished by using digital and laser systems. These devices can also stimulate accurate views from any particular perspective in space. It also takes viewers on a virtual flight that goes beyond the solar system and into interstellar and intergalactic space.
There are other variations of the screen configurations and seating arrangements that are quite common. These configurations can range from the traditional horizontal domed screen to concentric seating that is located around a central projector for distorted or tilted domes. This is also present in auditorium seating and wraparound screens.
What are Sky Shows?
Sky shows are basically planetarium theatre programs that are offered to the general public. These programs are held on a regular schedule. The shows also have themes that are focused on space topics or other astronomical themes, including the cosmologies of ancient cultures, the future of life on Earth, and the extinction of dinosaurs.
There is also an aim to achieve total computer automation of these programs that should combine cued music, visual display, pre-recorded narration, and other sound effects. There are also large planetariums that use technologically advanced multimedia installations. These installations are usually supplemented with science programs that feature pure entertainment content along with spreading information.
History of Planetariums
It should be noted that the term ‘planetarium’ was originally used to describe a kind of mechanical model. The purpose of this model was to portray the motions of the orbits of the planets and their moons. These models were made for the purpose of exhibition and teaching.
The models were also mounted on wire rods for support and geared at a central pedestal. Stellarium is also an open-sourced free software planetarium. One can download the Stellarium application to experience the world of astrophysics in sharper colours!
Several models also consisted of moons that were known at the time of the construction. These are also known as orreries, after one of the English sponsors of a mini planetarium that was built in 1712. Orreries can be quite accurate and elaborate. The Deutsches Museum planetarium was unveiled to the public in 1923. It features the Zeiss projector and was officially opened two years after the opening of the museum. Many visitors described the planetarium as a schoolroom that is located under the domains of heaven.
The special educational sky shows are held in the planetarium for school children. This is a vital part of the program in most installations. There are also astronomy museum lessons given to college and university classes. The facilities can also be used for other lectures or courses given under adult continuing education programs.
The Planetariums in the World
There are several famous and astonishing planetariums located all across the globe.
Nagoya City Science Museum Planetarium
The Nagoya City Science Museum Planetarium is located in Nagoya City in Japan. This is the largest planetarium in the world as it hosts a huge metal dome that has a diameter of 35 meters. It also houses around 350 seats under a single massive dome screen.
In the largest planetarium, viewers can sit back and recline in those seats to look at the thousands of stars that mirror the night sky. One can also watch several exciting celestial events like meteor showers and eclipses on that screen. The high-quality sound system also adds to the experience and makes one believe that he or she is travelling through space.
L’Hemisferic
The L’Hemisferic planetarium is located in Valencia, Spain. In this planetarium museum, viewers can view the incredible beauty of the night sky. Originally, the planetarium was designed to function as a centrepiece of the City of Arts and Science that is a centre for science and culture. The complex was also supposed to have an aquarium and a landscaped garden.
There is right now a reminiscent of a giant eye, the building has a transparent eyelid that closes and opens over the concrete eyeball, which is located in the centre. There is also a pool of water that surrounds this entire feature.
There is an excellent IMAX theatre located inside the eyeball of this planetarium museum. And the planetarium is also known as the ‘eye of knowledge.’ Viewers can enjoy watching a 3D display that would transport them into the depths of space on a 900 meters concave screen.
Adler Planetarium
The Adler Planetarium is located in Chicago, United States of America. It is present right on the water of Lake Michigan. It has an excellent view of the Chicago skyline. The Adler Planetarium was the first planetarium that was built in the western hemisphere.
Currently, this planetarium is home to three different theatres, including the Definiti Theater, the Samuel C. Johnson Family Star Theater, which had HD and 3D equipment, and the Grainger Sky Theater, which is the biggest and most technologically advanced theatre.
Apart from all this, the theatres are also equipped with the latest sound systems and projectors that enhance the experiences of the visitors. One can also view various special exhibits and engage his or her mind in the observatory.
There is also a Gates Planetarium that is located in Denver, Colorado, United States of America.
Fun Facts about the Indira Gandhi Planetarium in Lucknow, India
Did you know that there is a renowned planetarium located in Lucknow, India? This is true and that planetarium is known as the Indira Gandhi Planetarium. This planetarium has the iconic shape of Saturn and is complete with five rings and 21 meters diameter for the spherical theatre space!
The entire building rests on a raised platform. It is also surrounded by several beautiful fountains. The guests have the option of visiting a space gallery inside the planetarium. The space gallery is filled with all sorts of information about Indian satellites. It is located on the ground floor.
The main auditorium of the planetarium also has a diameter of 15 meters. This is where the guests can watch several video projects on different topics, including the Chandrayaan mission to the moon. Most of the shows are presented in Hindi. But guests can also catch some shows in English.