Angstrom star = 1.000 014 95 × 10−10 m

Value
1.000 014 95 × 10−10
Unit
m
Uncertainty
0.000 000 90 × 10⁻¹⁰
Copy-ready
1.00001495e-10

A historical X-ray wavelength unit (Å*) defined from the tungsten Kα₁ line, close to but not equal to one ångström.

Still met in older X-ray crystallography tables; convert with this value rather than treating Å* as 10⁻¹⁰ m.

NIST, Fundamental Physical Constants — Complete Listing (2022 CODATA adjustment), retrieved 2026-07-26.

Electrical, thermal and X-ray constants

Angstrom starConductance quantumCopper x unitElectron charge to mass quotientFermi coupling constantFirst radiation constantHartree energyJosephson constantLattice parameter of siliconLattice spacing of ideal Si (220)Loschmidt constant (273.15 K, 101.325 kPa)Magnetic flux quantumMolar mass constantMolar mass of carbon-12Molar Planck constantMolar volume of siliconMolybdenum x unitNeutron-proton mass differenceProton charge to mass quotientQuantum of circulationSackur-Tetrode constant (1 K, 101.325 kPa)Second radiation constantVon Klitzing constantWeak mixing angleWien frequency displacement law constantW to Z mass ratio

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All physical constants

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