Astronomy & Space
Basic

Light-Year

Distance light travels in one year.

Formula

1 ly=c×1 year1\,ly = c\times 1\,\text{year}

Variables

cSpeed of light

Example

≈ 9.46×10¹² km

Did You Know?

A light-year is about 9.5 trillion kilometres, yet the nearest star beyond the Sun is over four of them away.

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