Question

What is the revolution period of the sun?

Answer 1

Hint: In the given question, we are required to find the revolution period of the sun. Before answering the problem, we are required to understand the meaning of the terms ‘revolution’ and ‘rotation’ clearly. Revolution of a planetary object refers to its movement in an elliptical orbit around another central spatial body.

Complete answer:
Revolution means movement around another body in a fixed path and rotation means the movement of the body on its own axis. Similarly, the Sun also revolves around the Milky Way galaxy in a fixed path and completes one revolution in a fixed interval of time. So, we have to find the fixed interval of time in which the Sun goes around the Milky Way galaxy.

The Sun also orbits the centre of the Milky Way at about $225$ kilometres per second, and our galaxy itself has a motion in its local Group of galaxies of about $100$ kilometres per second. Our Local Group, in turn, has a speed of about $220$ kilometres per second relative to the Super Cluster it resides in, and there are further layers of motion beyond that.The Sun goes around the Milky Way in nearly two hundred and twenty six million years.

Therefore, the period of revolution of the sun around the Milky Way galaxy is two hundred and twenty six million years.

Note: We should know about the planetary motions and their time durations to solve the problem. We can also provide an answer to the question if we know the distance of the Sun’s orbit and speed at which the sun goes round the Milky Way galaxy. We should always keep an open mind while attempting such theoretical questions that have open ended answers.