Light-year to Astronomical unit
Convert Light-year to Astronomical unit instantly. Free online astronomy unit converter with exact formula, conversion table and FAQ.
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Astronomy Converter
Convert astronomical length, mass, time, and distance units by compatible family.
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Formula
astronomical unit = light-year × 63241.07708
light-year = astronomical unit × 1.58125074e-5
Conversion table
| 1 ly | 63241.07708 AU |
| 5 ly | 316205.3854 AU |
| 10 ly | 632410.7708 AU |
| 20 ly | 1.26482154e+6 AU |
| 50 ly | 3.16205385e+6 AU |
| 100 ly | 6.32410771e+6 AU |
| 500 ly | 3.16205385e+7 AU |
| 1,000 ly | 6.32410771e+7 AU |
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Frequently asked questions
What is the source unit in this conversion?
The source unit is the light-year (ly). A light-year is the distance light travels in one Julian year through a vacuum.
What is the destination unit in this conversion?
The destination unit is the astronomical unit (AU). An astronomical unit (AU) is the mean Earth-Sun distance, about 149.6 million kilometers.
How do I convert light-year to astronomical unit?
Multiply the light-year value by 63241.07708. For example, 10 ly × 63241.07708 = 632410.7708 AU.
Is the light-year to astronomical unit conversion exact?
Yes. Both units have a fixed, defined relationship to the astronomy converter's distance base unit, so the conversion factor is exact rather than a measured approximation.
Where is this conversion commonly used?
It's used in astronomy, physics, and space science whenever a distance value expressed in light-year needs to be compared with, or reported in, astronomical unit.
Can I convert astronomical unit back to light-year?
Yes. Multiply the astronomical unit value by 1.58125074e-5 to get light-year.
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About this conversion
This page converts light-year (ly) to astronomical unit (AU) within the astronomy converter.
A light-year is the distance light travels in one Julian year through a vacuum.
An astronomical unit (AU) is the mean Earth-Sun distance, about 149.6 million kilometers.
The formula is astronomical unit = light-year × 63241.07708, based on each unit's fixed relationship to the astronomy converter's distance base unit.
The conversion is exact, since it relies on a fixed numerical ratio between the two units rather than a measured or approximate value.
Use the calculator above for instant results, or the table below for common light-year values already converted to astronomical unit.