Nanometers to Light-years (nm to ly)

1 nanometer equals 1.057000834×10⁻²⁵ light-years (rounded).

1 nanometer = 1.057000834×10⁻²⁵ light-years

How to convert nanometers to light-years

To convert nanometers to light-years, multiply the number of nanometers by 1.057000834×10⁻²⁵. The factor is rounded to 10 significant digits. To go the other way, multiply light-years by 9.460730473×10²⁴ (rounded).

light-years = nanometers × 1.057000834×10⁻²⁵

Example: 10 nanometers = 1.057000834×10⁻²⁴ light-years.

About these units

Nanometer (nm)

Metric (SI)Current unit

One billionth of a meter. Used for the wavelength of light (visible light is about 400–700 nm) and for chip feature sizes.

Greek for dwarf gave nano- its name, and the nanometer was once called something clumsier: the millimicrometre, or more often the millimicron, written mμ, since it is a thousandth of a micrometer. The prefix nano- was among those officially adopted when SI prefixes were first introduced in 1960, and the nanometer grew into the standard unit for optics and microelectronics. It sits a factor of ten above the older ångström, which is 0.1 nm and is still used for atomic distances.

Visible light spans roughly 400 to 700 nm, which is why color and spectroscopy are quoted this way. A helium atom is about 0.06 nm across and a ribosome about 20 nm. Chip makers have used nanometers since the late 1980s in names for manufacturing generations such as 32 nm and 22 nm. Those are labels for successive generations in the industry roadmap, and they describe typical feature sizes rather than one exact measurement. Readers should also beware that nm is sometimes written informally for the nautical mile.

1 nanometer = 1×10⁻⁹ meters (exactly).

Sources: Wikipedia: Nanometre; Wikipedia: Metric prefix; Wikipedia: Nautical mile

Light-year (ly)

AstronomicalCurrent unit

The distance light travels in one Julian year: exactly 9,460,730,472,580,800 meters (about 9.46 trillion km).

Despite the name, a light-year measures distance rather than time, and its coinage is a little later than most people assume. Friedrich Bessel measured the distance to the star 61 Cygni in 1838 but did not use the unit himself. The light-year appeared in print in 1851, in a German article by Otto Ule, who explained its odd use of a time word by comparing it to saying that a place is an hour's walk away.

The International Astronomical Union defines it as the distance light travels in a vacuum in one Julian year of 365.25 days, about 9.46 trillion kilometers. NIST lists it as 9.460 73 times 10 to the 15th meters. Light-years dominate popular science, while professional astronomers mostly prefer the parsec, about 3.26 light-years. For scale, Proxima Centauri, the nearest star to the Sun, is about 4.24 light-years away, and the Milky Way is roughly 100,000 light-years across.

1 light-year = 9.460730473×10¹⁵ meters (approximately).

Sources: Wikipedia: Light-year; NIST Guide to the SI, Appendix B.8: conversion factors

Related conversions

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