According to the Newtonian perspective on gravity, gravity is a universal force that tracks every single piece of matter. This forces proportional to the mass of the pieces of matter, but also proportional to the reciprocal of the distance between the two masses. This relationship can be well seen in this equation, in which F is gravitational force, which according to Newton's third law acted upon both massages mutually on different directions but same in magnitude. GE is a gravitational constant. The M's are the two masses attracting each other and R is a straight line between the two points masses. The law of universal gravitation was derived by Sir Isaac Newton with help from other contemporary physicists, most notably Robert Huck from other existing equations such as the Kepler's laws on planetary motion, which is explained in more detail in our other video. The exact derivation of the law of ununiversal gravitation is long and will not be fully explained in this video, but if you're curious, pause the video here and take a screenshot of these simplified versions of the derivation of universal gravitation from Kepler's laws. Newton presented an indefinite investigation of the law of universal gravitation in his book Pinchipia in the year 181686 and was a result of his work ranging over decades. For a fact, Newton actually did watch an apple fall from the tree, but it wasn't the decisive eureka moment as described by popular myth. From Newton's original universal law on gravitation comes a range of different equations concerning gravitation, many of which are also discovered by Newton and covered in Pinchipia. These equations enable us to calculate the gravitational potential energy or below velocity, escape velocity, gravitational field strength and way more. The Schwarzschild radius, the radius of spherical non-spending blockhole with a point mass at its center, is derived from general relativity, but the same solution could be obtained using Newton's laws, which by the way was done by the Marquis de la Place in the 18th century. Nowadays many astronomers and physicists still use Newton's laws on gravitation as a handy tool. However, with the theory of general relativity proposed my Albert Einstein in 1915, most theoretical physicists consider Newton's laws as limited in comparison to the Einstein field equations. Because Newton's laws fail to explain phenomena such like the procession of parachelion and the deflection of light by gravity. Regardless, Newton's laws are way simpler than Einstein's field equations, and Newton's laws are still widely applicable rough descriptors of most situations not involving relativistic velocities, warps space-time or extremely massive bodies. The calculator linked them to the description provides a tool for any users to calculate the Newtonian gravitational force, gravitational potential energy, and escape velocities with the initial values of two masses and the distance to each other. Many parameters relating to the Newtonian gravitational relate only to these three factors, masses of two objects, and the distance from each other, which means that this equation is perfectly suited for a calculator. Check out the calculated in the link in the description, along with other videos about other laws in astrophysics.