Question

What is a light year? The distance between the Earth and the Sun is 150 ~ 10 km
Express this distance in light years.
Differentiate between the following:​

Answer 1

Answer:

Stars other than our sun are so far distant that astronomers speak of their distances not in terms of kilometers or miles – but in light-years. Light is the fastest-moving stuff in the universe. If we simply express light-years as miles and kilometers, we end up with impossibly huge numbers. But the 20th century astronomer Robert Burnham, Jr. – author of Burnham’s Celestial Handbook – devised an ingenious way to portray the distance of one light-year and ultimately of expressing the distance scale of the universe, in understandable terms.

He did this by relating the light-year to the astronomical unit – the Earth-sun distance.