Question

How far is the moon in light-years from earth?

Answer 1

Step 1: Given

Light Years

1. A light-year is a unit used to measure astronomical distance.
2. One light-year is defined as the total distance traveled by light in one year.
3. One light-year is equal to $9.461\times {10}^{15}m$

Step 2: Distance between moon and earth

1. The average distance between the Earth and the Moon is $384400km$.
2. Light travels at $300,000$ kilometers per second.
3. Then the time is taken to cover the distance between the Earth and the Moon will be.
4. $t=\frac{384400}{300000}=1.3sec$
5. This is the time taken by light to travel the distance between the Earth and the Moon.

Hence the distance between the Earth and the Moon is $1.3$ light-second.