Theories of the universe 

==Big bang theory== is the leading explanation on how the universe began. All matters was compacted into a hot, dense, tiny ball called singularity.

==Steady state universe theory== proposed that the universe has been present ever since and therefore has no beginning and has no end.

==Oscillating universe theory==, another Bigbang will occur when the universe starts to run down.

==Nebular hypothesis or planetesimal theory== as gas swirled around, Eddie's of gas caused the formation to run down

Fission theory bursting of sun sent out planets

Capture theory planets and moons were wandering around and were captured by the sun.

==Accretion theory== small chunks materials gradually combined and formed earth, then more chunks formed the moon.

==Planetary collision theory== earth collided with small formed the planets and moons

==Stellar collision theory== two stars collided with a small planet producing the moon

==Gas cloud theory== gas cloud is pulled by sun's gravity, the formed into planets and moons.