Convert length and distance units — meters, feet, inches, kilometers, miles, light years and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 nm | 6.684e-24 au | |
| 0.01 nm | 6.684e-23 au | |
| 0.1 nm | 6.684e-22 au | |
| 1 nm | 6.684e-21 au | |
| 5 nm | 3.342e-20 au | |
| 10 nm | 6.684e-20 au | |
| 50 nm | 3.342e-19 au | |
| 100 nm | 6.684e-19 au | |
| 1000 nm | 6.684e-18 au |
Multiply the number of Nanometers by 6.6845×10-21 to get Astronomical Units. Formula: au = nm × 6.6845×10-21. Example: 10 nm × 6.6845×10-21 = 6.6845×10-20 au. To reverse, divide Astronomical Units by 6.6845×10-21 to get Nanometers.
| Nanometer (nm) | Astronomical Unit (au) |
|---|---|
| 0.001 nm | 6.6845×10-24 au |
| 0.01 nm | 6.6845×10-23 au |
| 0.1 nm | 6.6845×10-22 au |
| 0.5 nm | 3.3422×10-21 au |
| 1 nm | 6.6845×10-21 au |
| 2 nm | 1.3369×10-20 au |
| 5 nm | 3.3422×10-20 au |
| 10 nm | 6.6845×10-20 au |
| 20 nm | 1.3369×10-19 au |
| 50 nm | 3.3422×10-19 au |
| 100 nm | 6.6845×10-19 au |
| 250 nm | 1.6711×10-18 au |
| 500 nm | 3.3422×10-18 au |
| 1000 nm | 6.6845×10-18 au |
| 10000 nm | 6.6845×10-17 au |
To convert Nanometer to Astronomical Unit, multiply by 6.6845×10-21. Example: 10 nm = 6.6845×10-20 au
To convert Astronomical Unit back to Nanometer, divide by 6.6845×10-21 (multiply by 1.496×1020). Use the swap button above.
Start with 100 Nanometers = 6.6845×10-19 au as your reference point. Scale up or down from there.
Astronomers measure spectral line wavelengths in nanometres to identify elements and measure redshift, while expressing stellar distances in AU or parsecs — both units in the same observation paper bridging atomic and cosmic scales.
Transmission spectroscopy of exoplanet atmospheres measures molecular absorption features at nanometre wavelengths while the exoplanet orbits at AU-scale distances from its host star — both units in the same Nature paper.
Solar physicists model how irradiance at specific wavelengths (in nm) varies with distance from the Sun (in AU). The conversion between these units is embedded in solar spectral irradiance databases used for climate and energy research.
Space telescopes specify detector sensitivity in nanometres while operational distances from Earth use AU. Both scales appear in the same instrument specification when defining wavelength coverage and orbital parameters.
1 AU = 1.496×10²⁰ nm — 150 quintillion nanometres. Physics educators use nm-to-AU to make the cosmic distance scale visceral: "The Earth-Sun distance expressed in nanometres is a 21-digit number."
Laser-based space communications specify wavelength in nanometres (1064 nm, 1550 nm) while link distances use AU for solar system missions — both units appear in the same space laser comm system design document.
The Nanometer is a unit of Length measurement (symbol: nm). 1 nm = 6.6845×10-21 au. Used in scientific and practical Length measurement applications.
The Astronomical Unit is a unit of Length measurement (symbol: au). It is part of an internationally recognised measurement system used alongside the Nanometer.
The nanometre owes its name to the Greek 'nanos' (dwarf) combined with 'metre'. The prefix 'nano' was formally adopted by the International Committee for Weights and Measures in 1960 as part of the SI prefix system. Before the nanometre became standard, atomic-scale scientists used angstroms (1 nm = 10 Å), a unit named after Swedish spectroscopist Anders Ångström. The nanometre rose to public prominence in the 1980s and 1990s alongside the emergence of nanotechnology and semiconductor manufacturing, where transistor feature sizes first crossed the nanometre threshold around 1995 with the 180nm process node. Today the nanometre defines the entire semiconductor industry — every chip generation is named by its nm node size.
The astronomical unit has ancient roots — Aristarchus of Samos attempted to measure the Earth-Sun distance around 270 BC. For centuries the AU was estimated using Venus transit observations. Edmond Halley organised the first coordinated international transit-of-Venus expedition in 1716. The modern value was determined by radar ranging to Venus in 1961. The IAU formally defined the AU as exactly 149,597,870,700 metres in 2012.
Common use: Nanometer to Astronomical Unit conversion is needed when working with international standards, scientific publications, or reference materials that use different unit systems for Length measurement.