Convert Microradians to Milliarcseconds

Convert Microradians (µrad) to Milliarcseconds (mas) instantly and accurately.

Microradians (µrad)
Milliarcseconds (mas)

Conversion Formula

mas = µrad × 206.2648062

About Microradians

A microradian (µrad) is one millionth of a radian (10⁻⁶ rad ≈ 0.206265 arcseconds). It is the standard unit for small angles in precision optics and structural monitoring. A 1 µm wavelength beam from a 1 mm aperture has a diffraction-limited half-angle divergence of ~1 µrad. Atmospheric seeing for ground-based telescopes is typically 2.4-9.7 µrad (0.5-2 arcseconds). Autocollimators resolve angular deviations to 0.05-1 µrad for machine tool alignment. Building tilt monitoring tracks µrad/day. 1 µrad ≈ 0.2063″ = 0.2063 arcseconds.

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.

Quick Reference Table

Microradians (µrad)Milliarcseconds (mas)
1 µrad206.265 mas
2 µrad412.53 mas
5 µrad1031.32 mas
10 µrad2062.65 mas
25 µrad5156.62 mas
50 µrad10313.2 mas
100 µrad20626.5 mas

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