Convert Milliarcseconds to Signs
Convert Milliarcseconds (mas) to Signs (sign) instantly and accurately.
Conversion Formula
sign = mas × 9.259259259e-9
About Milliarcseconds
A milliarcsecond (mas) is one thousandth of an arcsecond - approximately 4.848 × 10⁻⁹ rad. It is the standard unit of precision astrometry. The ESA Hipparcos satellite measured stellar positions to ~1 mas; its successor Gaia achieves 7-100 µas for bright stars. A parallax of 1 mas corresponds to a distance of 1 kiloparsec (3,260 light-years). Very Long Baseline Interferometry (VLBI) resolves well below 1 mas, imaging structures around supermassive black holes. 1 mas = 10⁻³ arcseconds ≈ 4.848 × 10⁻⁹ rad.
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.
Quick Reference Table
| Milliarcseconds (mas) | Signs (sign) |
|---|---|
| 1 mas | 9.259 × 10-9 sign |
| 2 mas | 1.852 × 10-8 sign |
| 5 mas | 4.63 × 10-8 sign |
| 10 mas | 9.259 × 10-8 sign |
| 25 mas | 2.315 × 10-7 sign |
| 50 mas | 4.63 × 10-7 sign |
| 100 mas | 9.259 × 10-7 sign |