Light-years to Astronomical Units (ly to au) Converter
1 Light-year equals 63,241.0771 Astronomical Units (1 ly = 63,241.0771 au). Convert Light-years to Astronomical Units with formula, table, and examples.
One light-year equals approximately 63,241 astronomical units. This is one of the most important astronomical conversions, connecting solar system scale (AU) with interstellar scale (light-years). The nearest star Proxima Centauri is 4.24 light-years or about 268,000 AU away.
How to Convert Light-years to Astronomical Units
- Take your value in Light-years
- Multiply by 63,241.0770842663
- Read the result in Astronomical Units
Common Light-years to Astronomical Units Conversions
| Light-years (ly) | Astronomical Units (au) | Status |
|---|---|---|
| 0.001 ly | 63.2411 au | |
| 0.01 ly | 632.4108 au | |
| 0.1 ly | 6,324.1077 au | |
| 0.5 ly | 31,620.5385 au | |
| 1 ly | 63,241.0771 au | |
| 2 ly | 126,482.1542 au | |
| 4.24 ly | 268,142.1668 au | |
| 5 ly | 316,205.3854 au | |
| 10 ly | 632,410.7708 au | |
| 50 ly | 3,162,053.8542 au | |
| 100 ly | 6,324,107.7084 au | |
| 1,000 ly | 63,241,077.0843 au | |
| 100,000 ly | 6,324,107,708.4266 au |
Good to Know About Light-years to Astronomical Units Conversion
The AU-to-light-year conversion reveals the cosmic loneliness of stars. Our solar system spans about 3 light-years including the Oort Cloud, but the nearest neighbor is 4.24 light-years away. Stars are islands separated by vast oceans of nothing.
Light-years to Astronomical Units: What You Need to Know
A light-year is 63,241 AU. The Sun's gravitational influence extends to about 100,000 AU (the Oort Cloud), roughly 1.58 light-years. So the solar system in its broadest definition spans about 3.16 light-years across. The nearest star system (Alpha Centauri) begins at 4.24 light-years.
What is a Light-year? ly
The distance light travels in one Julian year (365.25 days) in vacuum. Exactly 9,460,730,472,580,800 meters. Used for interstellar distances.
Learn more about Light-year →What is a Astronomical Unit? au
Exactly 149,597,870,700 meters by IAU 2012 definition. Roughly the average distance from the Earth to the Sun. Used for distances within our solar system.
Learn more about Astronomical Unit →Going the other way? Use our Astronomical Units to Light-years converter.
Light-years to Astronomical Units FAQ
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One light-year contains approximately 63,241 AU. This means light from the Sun takes about 8 minutes to travel 1 AU but about 1 year to travel 63,241 AU.
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Proxima Centauri is about 268,370 AU (4.244 light-years) from the Sun.
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AU for solar system distances (planets, asteroids, spacecraft). Light-years for stellar and galactic distances. The crossover is roughly at the Oort Cloud boundary.
Non-Frequently Asked Questions About Light-years to Astronomical Units
Questions nobody should ask - but someone did.
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The Sun's diameter is about 0.00929 AU. A basketball is 24 cm. At this scale, 1 AU = 25.8 m. The nearest star (268,370 AU) would be 6,924 km away - roughly New York to London. A basketball in New York and one in London. That is how empty space is.
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At 100 km/h, driving 1 light-year (9.461 x 1012 km) would take about 10.8 million years. That is longer than the entire Cenozoic era. Your car would fossilize several times before arriving.
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The Oort Cloud extends from roughly 2,000 to 100,000 AU (about 0.03 to 1.58 light-years). So the outermost edge is about 1.58 light-years from the Sun. That means comets from the Oort Cloud start their journey about 1/3 of the way to the nearest star. Space is almost entirely nothing.
Related Articles About Light-years to Astronomical Units
Need the reverse? Use our Astronomical Units to Light-years converter. See all Length & Distance converters.