40ᵗʰ B.P.S.C. (Pre) 1995

Time taken by the Sun to revolve around the centre of our galaxy is –

a2.5 crores years
b10 crores years
c25 crores years✓ Correct
d50 crores years

Explanation

Due to an average distance of about 7.94 KPC or 25.896 (about 26) thousand light years from the galactic center and an average speed of about 720 thousand km per hour, the Sun takes nearly 22.5 to 25 crores years to complete one revolution. This period of revolution is called the Cosmic Year. Hence, as the nearest option, option (c) will be the required answer.

general-geography