What are the differences between stars, planets, and galaxies?

1 Answer
Feb 14, 2017

I tried this:


Stars are big balls of gas (mainly Hydrogen) undergoing thermonuclear fusion and releasing, in the process, a lot of energy in form of light and radiation.

Planets are basically rocks orbiting a star and they do not emit energy (even if they can have a hot inner core).

Galaxies are group of stars that can have around them planets and together form a structure that can be separated from the surrounding space as having a definite shape. Normally galaxies rotate while moving in space,