The Big Bang
What is the famous equation that describes how matter is formed from the energy of the Big Bang?
E=mc^2
Observable universe
Everything we are able to see in the universe.
What would the universe be like if gravity were stronger?
Everything would be black holes.
How will the universe look 100 billion years form now?
It will go dark.
When were the hydrogen atoms in water made?
Moments after the Big Bang.
When astronomers say that the universe became transparent 380,000 years after the Big Bang, what do they mean?
That light was forming.
When did the first galaxies form?
1 billion years after the Big Bang.
What are three pieces of evidence scientists use to support the Big Bang?
1. The universe is expanding. 2. Cosmic Microwave Background Radiation 3. The abundance of different elements in the universe.
How old is the universe? How do scientists know?
13.7 billion years ago, because you can observe only those parts of the universe fro which light has had time to reach the Earth.
When did the first stars form?
2 million years after the Big Bang.
Why is the expansion of the universe accelerating?
Because of dark energy.
What did Edwin Hubble discover about galaxies at Mt. Wilson Observatory in 1929?
He discovered that the universe is expanding.
During the first three minutes of the universe's existence, the elements _______ and ______ also formed.
Helium and Lithium.
What was the first element that formed?
Hydrogen
What would the universe be like if gravity were weaker?
The structure and size of the universe would be different.