The Big Bang
Did You Know?
The Big Bang occurred 13.8 billion years ago!
The Beginning
The Big Bang theory describes how the universe began as an extremely hot, dense point about 13.8 billion years ago and has been expanding ever since. At the moment of the Big Bang, the entire universe was compressed into a singularity - a point of infinite density. In the first fraction of a second, the universe expanded faster than the speed of light in an event called inflation.
Evidence
Multiple lines of evidence support the Big Bang theory: the cosmic microwave background radiation (leftover heat from the Big Bang), the observed expansion of the universe, the abundance of light elements (hydrogen and helium), and the large-scale structure of the universe. The cosmic microwave background, discovered in 1965, is considered the 'smoking gun' evidence for the Big Bang.
Timeline
Key moments in the Big Bang timeline:
- 0 seconds: Big Bang - universe begins
- 10⁻³⁶ seconds: Inflation - rapid expansion
- 3 minutes: First atoms form (hydrogen, helium)
- 380,000 years: Universe becomes transparent - light can travel
- 200 million years: First stars form
- 9 billion years: Our Solar System forms
Amazing Facts
The universe is 13.8 billion years old
This fact reveals the incredible scale and wonder of our universe.
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The cosmic microwave background is 2.7 K
This fact reveals the incredible scale and wonder of our universe.
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The universe is still expanding today
This fact reveals the incredible scale and wonder of our universe.
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The Big Bang created space and time
This fact reveals the incredible scale and wonder of our universe.
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Timeline
Big Bang
Universe begins from a singularity
Inflation
Universe expands faster than light
Nucleosynthesis
First atoms form
Recombination
Universe becomes transparent
First Stars
Stars begin to form
Your Next Jump
Continue your journey through the cosmos