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Only one thing is impossible for God: To find any sense in any copyright law on the planet.
Clément Ader demonstrated the first two-channel audio system in Paris in 1881 Stereophonic sound or, more commonly, stereo, is a method of sound reproduction that creates an illusion of directionality and audible perspective. This is usually achieved by using two or more independent audio channels through a configuration of two or more loudspeakers in such a way as to create the impression of sound heard from various directions, as in natural hearing. Thus the term “stereophonic” applies to so-called “quadraphonic” and “surround-sound” systems as well as the more common two-channel, two-speaker systems.
Stereo sound systems can be divided into two forms: The first is “true” or “natural” stereo in which a live sound is captured, with any natural reverberation or ambience present, by an array of microphones. The signal is then reproduced over multiple loudspeakers to recreate, as closely as possible, the live sound.
Stereophonic sound attempts to create an illusion of location for various sound sources within the original recording.
The History of Stereo
Clément Ader demonstrated the first two-channel audio system in Paris in 1881, with a series of telephone transmitters connected from the stage of the Paris Opera to a suite of rooms at the Paris Electrical Exhibition, where listeners could hear a live transmission of performances through receivers for each ear.
This two-channel telephonic process was commercialized in France from 1890 to 1932 as the Théâtrophone, and in England from 1895 to 1925 as the Electrophone. Both were services available by coin-operated receivers at hotels and cafés, or by subscription to private homes.
Images provided by Das Programm.
The Hubble Space Telescope is a space telescope that was launched into low Earth orbit in 1990, and remains in operation. With a 2.4-meter (7.9 ft) mirror, Hubble’s four main instruments observe in the near ultraviolet, visible, and near infrared spectra. The telescope is named after the astronomer Edwin Hubble.
Hubble’s orbit outside the distortion of Earth’s atmosphere allows it to take extremely high-resolution images with negligible background light. Hubble has recorded some of the most detailed visible-light images ever, allowing a deep view into space and time. Many Hubble observations have led to breakthroughs in astrophysics, such as accurately determining the rate of expansion of the universe.
Hubble’s Impressive Shots
Although not the first space telescope, Hubble is one of the largest and most versatile, and is well known as both a vital research tool and a public relations boon for astronomy. The HST was built by the United States space agency NASA, with contributions from the European Space Agency, and is operated by the Space Telescope Science Institute. The HST is one of NASA’s Great Observatories, along with the Compton Gamma Ray Observatory, the Chandra X-ray Observatory, and the Spitzer Space Telescope.
Hubble is the only telescope designed to be serviced in space by astronauts. After launch by Space Shuttle Discovery in 1990, four subsequent Space Shuttle missions repaired, upgraded, and replaced systems on the telescope.
Space telescopes were proposed as early as 1923. Hubble was funded in the 1970s, with a proposed launch in 1983, but the project was beset by technical delays, budget problems, and the Challenger disaster. When finally launched in 1990, Hubble’s main mirror was found to have been ground incorrectly, compromising the telescope’s capabilities. The optics were corrected to their intended quality by a servicing mission in 1993.