When does a total eclipse happen?

A Roman Scientist who attempted to examine the motion of planets using mathematical formula. He preserved the principles of Geocentrism, and uniform circular motion, where he added Epicycles, Deferent, and Equant to fully explain the motion of planets.

An Italian Scientist who discovered the Jupiter's four largest satellites, or moons using his telescope. He also discovered that Venus exhibits different phases just like our Moon.

A Greek Philosopher, Scientist, and Polymath who proposed that the Earth was the center of the Universe, where heavens must move in uniform circular motion.

Though he preserved the uniform circular motion that planets follow on their motion, this Renaissance Polymath, a great Scientist, concluded that the Sun, not the Earth, was the center of the Universe, known as Heliocentrism.

In the concept of Vertical motion, he believed that the velocity of a body is inversely proportional to the time it covers to travel certain height.

In the concept of horizontal motion, he believed that there is no need to apply force for the object continuously move.

In the concept of projectile motion, he believed that there is resistance on a medium that respond to the movement of the body. He called this antiperistasis.

In the concept of 1st Law of Motion, he believed that there is necessary force to move a stationary body and to stop the object.

In the concept of 1st Law of Motion, h believed that in order to keep body at rest, Inertia is present.

In the concept of 1st Law of Motion, he believed that Inertia is the resistance of motion thus, body remains at rest without external force acted upon on it. This external force is also the reason that keeps the body in motion.

This phenomenon of light shows different spectral colors once light passes through a medium called prism. This is where light separates into bands of colors.

This phenomenon of light is when it hits a barrier, and turns back resulting to an angle of incidence, where incident ray is equal to the normal ray, producing erected image, virtual, laterally reversed, same size as the object, and apparently found behind the mirror.

This phenomenon of light happens when the angle formed between the incident ray and normal ray in not equal thus, producing an illusion. This happens because the light changes its direction as it hits different medium.