Top definition whale unknown noun; a wealthy patron to a casino, gets paid special attention by a casino host so the patron will feel comfortable to gamble more money.
The age of Earth is approximately one-third of the age of the universe. An immense amount of geological change has occurred in that timespan, accompanied by biological change. Earth formed around 4.54 billion years ago by accretion from the solar nebula. Volcanic outgassing probably created the primordial atmosphere and then the ocean; but the atmosphere contained almost no oxygen and so would have been toxic to most modern life including humans.
Various theories have been proposed to explain how the Moon formed. The most widely accepted scenario begins shortly after the Earth formed about 4.6 billion years ago. At this time, an object about the size of Mars struck the Earth. This early planet, which has been named Theia, was partially absorbed into the Earth, but a large amount of debris was also sprayed out into space.