| George Biddell Airy’s Transit Instrument | |
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Origin |
George Biddell Airy |
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Type |
Mounted Telescope |
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Effects |
Allows user to see orientation of mass according to any vector |
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Downsides |
Diffraction or refraction through the lenses displaces actual surroundings |
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Activation |
Looking into |
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Section |
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| [Source] | |
Origin[]
Sir George Biddell Airy (27 July 1801 – 2 January 1892) was an English mathematician and astronomer, as well as the Lucasian Professor of Mathematics from 1826 to 1828 and the seventh Astronomer Royal from 1835 to 1881. His many achievements include work on planetary orbits, measuring the mean density of the Earth, a method of solution of two-dimensional problems in solid mechanics and, in his role as Astronomer Royal, establishing Greenwich as the location of the prime meridian.
At the Cambridge Observatory Airy soon showed his power of organisation. The only telescope in the establishment when he took charge was the transit instrument, and to this he vigorously devoted himself. Airy's writings during this time are divided between mathematical physics and astronomy. The former are for the most part concerned with questions relating to the theory of light arising out of his professorial lectures, among which may be specially mentioned his paper On the Diffraction of an Object-Glass with Circular Aperture, and his enunciation of the complete theory of the rainbow.
The resolution of optical devices is limited by diffraction. So even the most perfect lens can't quite generate a point image at its focus, but instead there is a bright central pattern now called the Airy disk, surrounded by concentric rings comprising an Airy pattern. The size of the Airy disk depends on the light wavelength and the size of the aperture. John Herschel had previously described the phenomenon, but Airy was the first to explain it theoretically.
This was a key argument in refuting one of the last remaining arguments for absolute geocentrism: the giant star argument. Tycho Brahe and Giovanni Battista Riccioli pointed out that the lack of stellar parallax detectable at the time entailed that stars were a huge distance away. But the naked eye and the early telescopes with small apertures seemed to show that stars were disks of a certain size. This would imply that the stars were many times larger than the Sun (they were not aware of supergiant or hypergiant stars, but some were calculated to be even larger than the size of the whole universe estimated at the time). However, the disk appearances of the stars were spurious: they were not actually seeing stellar images, but Airy disks. With modern telescopes, even with those having the largest magnification, the images of almost all stars correctly appear as mere points of light.
Effects[]
Shows the distribution of mass in any system or area, usually larger for more detail. Displays with arrows the direction of any velocity moments, and dots to show concentrated areas of greater mass. Staring at a point for too long will imprint the Airy disk at the center of the lens into the actual, distorting matter around the focus.