# Law of universal gravitation

Introduction

Law of universal gravitation was first discovered by Isaac Newton in 1687. It mainly refers to a physical law that involves gravitational attraction of body masses. The law assists in establishing how different body masses have downward acceleration caused by earth’s upward acceleration. For this reason, law of universal gravitation has assisted in explaining the dynamics of remote astronomical objects. Astronomical objects involve speed and velocity to assist in motion.  In addition, acceleration of objects assist in ensuring distance is not the main variable associated in magnitude of a gravitational force.

n trying to prove that astronomical objects really depend on gravitational force, mathematics of circular motion has greatly been applied. Astronomical objects involve comparison to the acceleration of the moon and acceleration of the earths objects. Gravitation helps in making conclusion that the two accelerations are inversely proportional. Further, conclusion involving distance separating earth centre and the object can be determined. Astronomical objects are sometimes confused with astronomical bodies, therefore, celestial bodies are used to differentiate the two.

Astronomical bodies refer to physical entities that have been confirmed to exist in space. Good examples include Themis and Neith. For astronomical bodies to be remote gravity is essential in maintaining different dynamics for example the sun which is the main astronomical body in the solar system requires gravitational forces to maintain simple, compound and extended objects such as exoplanets, planetary systems and circumstellar matter. Satellites also require gravitational forces just like the other astronomical bodies. The only difference is that they require the forces for maintaining close binaries and reflection nebulae.

Newton’s law of universal gravitation is truly a universal force that corresponds to both the earth and forces and astronomical bodies. This is mainly evidenced by the forces that exist between two point masses and their gravitational constant. The value of gravitational constant mainly depends on first point mass {m1}, second point mass {m2} and the distance that exists between the two point masses.

Newton and several other scientists who have come up have argued that law of universal gravity exists in the entire universe since acceleration which is essential in all astronomical bodies. In addition, gravitational forces are also essential in gravitational bodies with spatial extent. Research has showed that bodies with spatial extent are located in masses enclosed with concentrated centre of mass distribution. This shows that individual masse tend to exert elements of gravitational force

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