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Symbol | Definition |
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≡ | exactly equal |
≈ | approximately equal to |
= | equal to |
digits | indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …) |
A pace is a unit of length consisting either of one normal walking step (~0.75 m), or of a double step, returning to the same foot (~1.5 m). Like other traditional measurements, paces started as informal units but have since been standardized, often with the specific length set according to a typical brisk or military marching stride.
The light-year is a unit of length used to express astronomical distances. It is about 9.5 quadrillion metres or 5.9 trillion miles. As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year (365.25 days). Because it includes the word "year", the term light-year is sometimes misinterpreted as a unit of time.