For 100 years we watched the planetariums. Here’s a brief story of how people brought stars indoors

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Picture: A small audience is quietly included in a darkened room. They were afraid because the great night sky shines above. They wonder – how will many after them do – what deception made the roof over their head disappear?

But this is a performance; Stars above inventive projections. For the first time, the public audience experienced an opt-mechanical planetary performance. The place is the newly opened Deutsches Museum in Munich, built to celebrate science and technology. The date is 1925. May 7

Visualizing the sky

All the time, cultural stars have been used by culture all over the world to help make sense of the world, to understand where we come from, and set our place in space.

People have been trying to recreate the movements of stars and planets since ancient times. In the 1700s, Orrery, a solar system clock model, was created. The word “planetarium” was invented to describe orraras that contained planets.

The one -room -sized Orrery example was built by the self -taught Friesian astronomer Eise Eisi. It still works today in Franceer, the Netherlands.

No man had ever been to the edge of the solar system to see this approach. Orreras and other mechanical models of the universe, such as the Globes of the Sky, feature images from impossible, external perspectives.

The first planetary

In fact, the desire of realistic images of stars and planets in the early twentieth century, which we actually see in the perspective as the pollution of growing cities reduced the view of the night sky.

People such as Oskar von Miller, the first director of the Deutsches Museum in Munich, Germany, wanted to return this vision of stars and planets to everyone. (Ironically but the previous von Miller’s career was an electrical engineer who stretched out the city lighting that contributed to light pollution.)

One early attempt to create this night sky was the Atwood sphere, located in Chicago in 1913.

About five meters in diameter, it was made of sheet metal perforated with a star map. From the inside, the light shines over 692 pinholes repeated the Chicago night sky. The whole structure could even be turned to model the stars motion.

The real stars demonstration is one thing. To represent planets whose positions in the sky are changing from night to night, are different. Von Miller and others at the Deutsches Museum knew that fixed holes could not reflect the complexity of the moving planet.

And what if the planets were displayed? If so would you not be the stars either? With this realization, a new type of planetarium was born, borrowing a name from previous orraras, but working completely differently.

The task of building such a device was given to the German optical company Carl Zeiss AG. After many failures, their first planetary projector was completed in 1923, and the first show at the Deutsches Museum a century ago.

Planetariums were the hit of society. For decades, they spread around the world – the first planetarium in the US opened in Chicago in 1930, and the first in Asia in Osaka, Japan in 1937.

The oldest Australian operative planetarium is Melbourne Planetarium, which has been released since 1965. Victoria museums are carrying out. Aotearoa in New Zealand Auckland Stardian Observatory has been in operation since 1997. In the current Planetarium, the current hemisphere has been operating in Montevideo, Uruguay, since 1955.

The changing pace of technology

The opto-mechanical projector of the planetarium remains a technological wonders of the modern world. Separate plates perforated with holes illuminate bright central light. Separate lenses concentrate each projection from one of these stars maps to fill the entire dome about 5,000 stars.

The sun, the moon and the planets have separate projectors, driven gears and rods, which mechanically calculate the position of the object in the sky at any time or place.

The opto-mechanical projector of the planetarium remains a technological wonders of the modern world. Separate plates perforated with holes illuminate bright central light. Separate lenses concentrate each projection from one of these stars maps to fill the entire dome about 5,000 stars.

The sun, the moon and the planets have separate projectors, driven gears and rods, which mechanically calculate the position of the object in the sky at any time or place.

Until 1990 The digital revolution was launched. With the advent of computers, the positions of the planets could now be calculated in a digital way. Melbourne Planetarium became the first digital planetary in the southern hemisphere. Installed by Digistar II.

This system created by the computer graphics company Evans and Sutherland replaced some of the lenses of previous projectors with a fish eye lens. One light fiber revolved throughout the dome so quickly that it seemed to create one image – albeit strangely green, and it became a stars field in a blurry green spots.

The less crunchy Starfield compromise was a 3D database with more than 9,000 stars. For the first time, the planetary audience could fly through space, far beyond the edge of the solar system.

Planetarium technology continues to develop. Today, most of the planetary works are operating through the video projection. Known as Fulldome, the output of several projectors is mixed together to create a seamless video, turning the planetarium into a refined 360 degree theater.

Gate to the stars

Astronomy has also changed over the last century. As Zeiss finished his first projector, astronomer Edwin Hubblas learned that other galaxies existed behind our Milky Way Galaxy.

Stars shown in 1925 In the dome of Munich, only a small part of the universe we know today.

Planetariums digital systems now contain data from telescopes and space agencies around the world. The audience can fly from the ground, the orbit orbit of the solar system planets and the moons and explore billions of well -known galaxies.

However, some things have not changed. From ORRERIES and Lantern slides to opt-mechanical and digital planetary astronomy communication has always been not only the latest scientific results.

The power of the planetarium over the past 100 years has been his ability to cause amazement and fear. It is involved in our long -term admiration for the great secret of the night sky.

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