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Sir Isaac Newton’s groundbreaking work in the 17th century led to the formulation of the law of universal gravitation. It explains that every point mass attracts every other point mass in the universe with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers. The formula for this force is expressed as \( F = G \cdot \frac{{m1 \cdot m2}}{{r^2}} \), where \( F \) represents the gravitational force, \( G \) is the gravitational constant, \( m1 \) and \( m2 \) are the masses of the two objects, and \( r \) is the distance between their centers.

This law is crucial in understanding celestial mechanics and the motion of planets around stars. By using this formula, we can calculate the force with which the Earth is attracted to the Sun, which helps to keep our planet in a stable orbit. If a change occurs in either the mass or the distance, then the gravitational force would correspondingly change.

Gravitational force is the attractive force between two masses. It's one of the four fundamental forces of nature and the one most of us are familiar with in our daily lives. Everything with mass exerts a gravitational pull on everything else with mass. The greater the mass, the stronger the force. Gravitational force keeps the planets in orbit around the Sun and governs the motion of galaxies and other large-scale structures in the universe.

It's important to note that this force acts over large distances and, unlike other forces, never becomes zero no matter how far apart two masses are. In our solar system, this gravitational force is what keeps the Moon orbiting Earth and satellites in orbit around our planet. The interplay of gravitational forces maintains the delicate balance necessary for the orbital paths of celestial bodies.

A black hole is a region of space where the gravitational pull is so intense that nothing, not even light, can escape from it. Black holes are formed from the remnants of a massive star that has ended its life cycle. After burning through the nuclear fuel in their cores, such stars undergo a supernova explosion. If the remaining mass is sufficient, the core collapses under its own gravity to form a black hole.

The transformation into a black hole does not alter the object’s mass if we assume no mass is lost during the supernova. However, the space it occupies, known as the event horizon, becomes incredibly small, reaching an infinitely dense point known as the singularity. Despite the dramatic changes in size and density, the gravitational influence on an orbiting body - such as a planet like Earth, if we're considering the hypothetical transformation of the Sun into a black hole - remains unchanged if the mass remains constant and no additional forces come into play.