Celestial Mechanics

What is celestial mechanics? is a branch of astronomy that deals with the motion of objects in outer space. Celestial mechanics applies principles of physics to astronomical objects.

History of celestial mechanics. Throughout history, many contributions made by many philosophers and physicists.

In 150B.C

Ptoemy studied the sky and came up with the theory of Deferent and epicycle where the epicycle was used to geometric model explain the variations in speed and directions of the motions of the moon sun and planets.\\\\

In 1543, Copernicus proposed that instead of the sun orbiting the earth the earth was orbiting the sun.

1609, Kepler tried to replicate Tycho Brahe results on the orbit of Mars but was unsuccessful.

Kepler’s laws on planetary motion

It was then he noticed that an imaginary line drawn from the planet to the sun swept out an equal amount of space in equal times =, regardless of where the planet was in orbit.

This led him to discover that the planets were in orbit.

Around 50 years old, Isaac newton discovered gravity.

Correction, Law of Gravitation since it does not work on black holes but only on planets

Orbits

The gravitationally curved trajectory of an objects, such as the trajectory of a planet around a star.

Why orbit

Kepler’s law of planetary motion

Newton’s law of gravitation

Einstein’s law

Kepler 1 law the orbit of a planet is an ellipse with the sun at one of the two foci( Closer to the objects it gets faster due to gravity.)

Kepler 2 A line segment joining a planet and the sun sweeps out equal areas at equal amounts of time.

Kepler 3 The square of a planet ’s orbital period is proportional to the cube of the length of the semi major axis of its orbit.

Newton’s law of gravitation

Every particle attracts every other particle in the universe with a force that is directly proportional to their product of the masses and inversely proportional to the square of the distance between their centres.

CONVERT EVERYTHING INTO SI UNIT FIRST BEFORE CALCULATING.

Einstein’s general relativity

It states that space and time are the same thing

Taking that spacetime is like a flat surface where objects push down on it, forming a concave like curve. This is what Einstein called gravity

An objects that repeatedly moves around the concave circularly is called an orbit