Astronomy: The scientific study
of the Galaxies, Stars, Nebulae, Solar Systems and the
Universe. It deals with a celestial objects
relationship to the Earth, size, position,
composition, motion, evolution and energy.
Astronomers use telescopes, satellites,
computers, space stations and observatories
to study the universe.
A celestial body we
call the Sun which emits light from nuclear
reactions at its core.