Answer:
The light will take 40,000 years to reach Earth
Step-by-step explanation:
When we look at the night sky we can see celestial bodies, such as planets and stars, which are very far from us! Measuring the distance between us and these celestial bodies would be costly if we used the units of distance meter (m) and / or kilometer (km), because the numbers would be very large. Therefore, the unit of distance used in astronomy is the Light Year.
Generally, by the presence of the word "year," this magnitude is mistaken for being a unit of time, but light year is a unit of distance and can be defined as the distance light travels over a year. Thus, we can conclude that if a star is located 40,000 light-years from Earth, the light of that star will take 40,000 years to reach Earth.