FACTS

An Astronomical unit (AU) is defined as the average distance between the sun and the Earth.

Mercury can be said to be about 1/3 of an AU from the Sun and Pluto averages about 40 AU from the Sun.

The average distance from the Sun to the Earth is approximately 93 million miles.

It takes approximately 8 minutes for light from the Sun to reach the Earth.

Light moves at a velocity of approximately 186 411.357 67 miles each second.

A light-year is a distance that light can travel in one year.

One light-year is equal to 5 903 026 326 300 miles.

Astronomers use units of a light-year to calculate distances from outside of our solar system.

The Milky Way Galaxy is approximately 150,000 light-years across.

The distance to the next nearest star, Proxima Centauri from Earth is 24 854 847 689 000 miles.

The distance to Proxima Centauri is 4.24 light-years.

The distance to our nearest galaxy, the Andromeda Galaxy is 13 048 795 037 000 000 000 miles.

The Andromeda Galaxy is 2.3 million light-years away.

Einstein's equation,  E = mc² is the equation of mass-energy equivalence where E is energy, m is mass, and c is the speed of light in a vacuum.

The Math of General Relativity is: (curvature of space-time) = (mass-energy density) * 8 pi G / c4.