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Length/Distance | Convert from point [Didot] to astronomical unit |
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Common Length Conversions Metric Length Conversions Unit Definition (point [Didot]) The point is a unit of length used by typographers and printers. When printing was done from hand-set metal type, one point represented the smallest element of type that could be handled, roughly 1/64 inch. Eventually, the point was standardized in Britain and America as exactly 1/72.27 = 0.013 837 inch, which is about 0.35 mm (351.46 micrometers). In continental Europe, typographers traditionally used a slightly larger point of 0.014 83 inch (about 1/72 pouce, 0.377 mm, or roughly 1/67 English inch), called a Didot point after the French typographer Firmin Didot (1764-1836). In the U.S., Adobe software defines the point to be exactly 1/72 inch (0.013 888 9 inch or 0.352 777 8 millimeters), a unit sometimes called the big point (bp). The German standards agency DIN has proposed that all these units be replaced by multiples of 0.25 millimeters (1/101.6 inch). Unit Definition (astronomical unit) An Astronomical Unit is approximately the mean distance between the Earth and the Sun. It is a derived constant and used to indicate distances within the solar system. Its formal definition is the radius of an unperturbed circular orbit a massless body would revolve about the sun in 2*(pi)/k days (i.e., 365.2568983.... days), where k is defined as the Gaussian constant exactly equal to 0.01720209895. Since an AU is based on radius of a circular orbit, one AU is actually slightly less than the average distance between the Earth and the Sun (approximately 150 million km or 93 million miles).
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