Our current research is about speed of time in various celestial bodies (especially planets and stars). The speed of time on celestial bodies (planets or stars) is a new concept which can be simply explained as: - Imagine you have landed on a certain planet and stayed there for some time. And after that you`ve gone to other planet whose size is different from the first planet. In both these cases, you will observe or experience that time is running at different speed, rate or interval. Or you will experience different time speed in both the planets (i.e. time is running faster on one planet and slower on another). This concept is known as the concept of speed of time on a planet. I also called it as “shrest theory”. For example, 1) if you are throwing an exactly same ball at an aim with same magnitude while being at two different planets, then you will observe that the ball will hit aim at different time (i.e. one will hit earlier and other will hit later) due to different value of speed of time in those two planets. 2) If you run/walk on two different planets with same magnitude, you will find that you are taking different time to reach the destination. 3) Astronaut walking on moon with equal magnitude will do movements with different velocity as compared to astronaut walking on earth due to different speed of time. In our research paper, I have mentioned all the factors and quantities on which the speed of time in celestial body depends. We have experimental examples and calculated proofs about my concept (including important formula for calculating speed of time in different planets). The formula of speed of time has expressed the value of speed of time in numerical value with suitable units, symbols and dimensions which are proving 100 % applicable on planets. My concept has revealed various answers about different time speeds occurring in different planets or celestial bodies and could also help us in understanding the nature of time more efficiently. To make this research possible, we have first studied the nature of time in a planet, observed the movements of various planets, collected all data and factors affecting speed of time, conducted several experiments (which is mentioned in my research paper) and finally created an equation/formula for speed of time on a planet. It will be our extreme honor, if higher authorities such as scientists, researchers, experts, explorers and innovative minds will read our concept, refer it for future use and suggest changes if any.