Question

At a distance of 4 LY, Proxima Centauri is the closest star to the Earth (other than the Sun). If it were located instead at a distance of 1 LY (1/4), its apparent brightness in our night sky would be

a. 16 times its present value
b. 10 times its present value
c. 6 times its present value

Answer 1

The apparent brightness of a star is inversely proportional to the square of its distance from Earth. This means that if the distance to a star is reduced to 1/4 of its original distance, its apparent brightness will increase by a factor of (4)^2 = 16.

Therefore, if Proxima Centauri were located at a distance of 1 LY (1/4 of its current distance), its apparent brightness in our night sky would be 16 times its present value.

So the correct answer is (a) 16 times its present value.