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Gran Atlas Aguilar (Spain, 1969/1970) Historical Atlas of China (Taiwan, 1980) The Historical Atlas of China (China, 1982) National Geographic Atlas of the World (United States, 1963–present) Pergamon World Atlas (1962/1968) Times Atlas of the World (United Kingdom, 1895–present) Dorling Kindersley Atlas of the World 1994–present
In mathematics, particularly topology, an atlas is a concept used to describe a manifold. An atlas consists of individual charts that, roughly speaking, describe individual regions of the manifold. In general, the notion of atlas underlies the formal definition of a manifold and related structures such as vector bundles and other fiber bundles .
The Atlas Coeli covers both hemispheres with 16 charts. The coordinate system is referred to equinox 1950.0 and the scale is 1° = 0.75 cm. There are six charts of the equatorial regions on a rectangular graticule, covering declinations from +25° to -25°; four charts for each hemisphere with straight, converging hour circles and concentric, equally-spaced declination circles covering ...
The speed of light in vacuum, commonly denoted c, is a universal physical constant that is exactly equal to 299,792,458 metres per second (approximately 300,000 kilometres per second; 186,000 miles per second; 671 million miles per hour).
Measuring the position and light of charted objects requires a variety of instruments and techniques. These techniques have developed from angle measurements with quadrants and the unaided eye , through sextants combined with lenses for light magnification, up to current methods which include computer-automated space telescopes .
The measurements of speed of light are also mentioned only to the minimum extent, i.e. when they proved for the first time that c is finite and invariant. Innovations like the use of Foucault's rotating mirror or the Fizeau wheel are not listed here – see the article about speed of light. This timeline also ignores, for reasons of volume and ...
The luminosity class ranged from I to V, in order of decreasing luminosity. Stars of luminosity class V belonged to the main sequence. [7] In April 2018, astronomers reported the detection of the most distant "ordinary" (i.e., main sequence) star, named Icarus (formally, MACS J1149 Lensed Star 1), at 9 billion light-years away from Earth. [8] [9]
The latter was the first atlas to chart both celestial hemispheres and it introduced the Bayer designations for identifying the brightest stars using the Greek alphabet. The Uranometria contained 48 maps of Ptolemaic constellations, a plate of the southern constellations and two plates showing the entire northern and southern hemispheres in ...