Light year is the distance light can travel in one year. One light year is equal to 9.4607×10¹² km. The statement, ‘a star is 8 light years away from the Earth’ mean that a star is 8×9.4607× 10¹² km =75.6856 km away from earth. By saying that a star is 8 light years away from the earth, we mean that the distance of this star from the earth is so much that the light from the star takes eight years to reach the earth.