What is one light year in meters?
One light year is 1 ly = 9.4607304725808e15 m exactly, about 9.46 trillion kilometres (the distance light travels in one Julian year).
Open the interactive PhysRef tool →Key facts
| Value | 9.4607304725808e15 m |
|---|---|
| Symbol | ly |
| In km | ≈ 9.461e12 km |
| Exactness | Exact (derived from c) |
| Source | IAU |
Frequently asked questions
How many meters is a light year?
1 ly = 9.4607304725808e15 m, the distance light travels in vacuum in one Julian year (365.25 days).
How many kilometers is a light year?
About 9.461 trillion km (9.4607304725808e12 km).
Is a light year a unit of time?
No. Despite the word year, a light year measures distance, not time.
Related pages
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