Convert Signs to Semicircles
Convert Signs (sign) to Semicircles (sc) instantly and accurately.
Conversion Formula
sc = sign × 0.1666666667
About Signs
An astrological sign equals 1/12 of a full circle - π/6 rad = exactly 30°. The zodiac divides the ecliptic into twelve 30° signs (Aries through Pisces), originating in Babylonian astronomy ~5th century BCE. Historical ecliptic longitude was expressed as sign + degrees: "Scorpio 12°" = 222°. The 30° spacing also appears in music theory: the circle of fifths has twelve equally spaced positions 30° apart, and the octave divides into 12 equal semitones. 1 sign = 30° = 1,800′ = π/6 rad = 533.3 NATO mils.
About Semicircles
A semicircle equals 1/2 of a full circle - exactly π rad = 180°. GPS and GLONASS transmit satellite orbital elements with latitude and longitude in semicircles, maximising angular resolution within 32-bit signed integers: ±2³¹ units span ±π rad with ~1.46 × 10⁻⁹ rad resolution per unit. Euler's identity e^(iπ) + 1 = 0 encodes exactly 1 semicircle of rotation in the complex plane, mapping 1 to -1 - often called the most beautiful equation in mathematics. 1 semicircle = π rad = 180° = 200 grad = 3,200 NATO mils.
Quick Reference Table
| Signs (sign) | Semicircles (sc) |
|---|---|
| 1 sign | 0.166667 sc |
| 2 sign | 0.333333 sc |
| 5 sign | 0.833333 sc |
| 10 sign | 1.66667 sc |
| 25 sign | 4.16667 sc |
| 50 sign | 8.33333 sc |
| 100 sign | 16.6667 sc |