Symbols and Abbreviations
The standard symbol for marking the arcminute is the prime (′) (U+2032), though a single quote (') (U+0027) is commonly used where only ASCII characters are permitted. One arcminute is thus written 1′. It is also abbreviated as arcmin or amin or, less commonly, the prime with a circumflex over it .
The standard symbol for the arcsecond is the double prime (″) (U+2033), though a double quote (") (U+0022) is commonly used where only ASCII characters are permitted. One arcsecond is thus written 1″. It is also abbreviated as arcsec or asec.
| Unit | Value | Symbol | Abbreviations | In radians (approx.) |
|---|---|---|---|---|
| Degree | 1⁄360 circle | ° | deg | 17.4532925 mrad |
| Arcminute | 1⁄60 degree | ′ (prime) | arcmin, amin, am, MOA | 290.8882087 µrad |
| Arcsecond | 1⁄60 arcminute | ″ (double prime) | arcsec, asec, as | 4.8481368 µrad |
| Milliarcsecond | 1⁄1,000 arcsecond | mas | 4.8481368 nrad | |
| Microarcsecond | 10−6 arcsecond | μas | 4.8481368 prad |
In celestial navigation, seconds of arc are rarely used in calculations, the preference usually being for degrees, minutes and decimals of a minute, written for example as 42° 25′.32 or 42° 25′.322. This notation has been carried over into marine GPS receivers, which normally display latitude and longitude in the latter format by default.
Read more about this topic: Minute Of Arc
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