How to Calculate Light Year
What is Light Year?
Converts light-years to kilometres, astronomical units (AU), and parsecs. 1 light-year = 9.461 × 10¹² km.
Formula
= 9.461 × 10¹² km = 63,241 AU
- AU
- AU value — Variable used in the calculation
Step-by-Step Guide
- 11 light-year = distance light travels in 1 year
- 2= 9.461 × 10¹² km = 63,241 AU
- 31 parsec ≈ 3.2616 light-years
Worked Examples
Input
1 light-year
Result
9.461×10¹⁵ m
Common Mistakes to Avoid
- ✕Assuming light-year is a unit of time
- ✕Confusing light-year with parsec
Frequently Asked Questions
Is a light-year a measure of time?
No — it is a unit of distance, despite the word "year". It is the distance light travels in one year.
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