Physical science Big Bang theory

Scientists think that the Big Bang occurred about

13.7 billion

Most scientists who study dark matter think that it is

A mix of ordinary matter and matter we haven't yet discovered

Universe

All the matter and energy that exists and all of space and time

After the Big Bang occurred, the universe

Began to cool

After the Big Bang, the universe became less dense and it's temperature

Cooled

The astronomer who concluded that the universe is expanding was

Edwin Hubble

Huge clumps of matter held together by....... eventually formed stars and galaxies

Gravity

The first element to form after the Big Bang was

Hydrogen

Big Bang Theory

Idea that explains how the universe formed

Scientists recently discovered that the universe

Is expanding even faster than before

The distance between galaxies appear to be getting

Larger

Dark matter

Matter that can be detected only by its effects on the motion of objects around it

From our point of view in the Milky Way galaxy, all other galaxies in the universe appear to be

Moving away from us

Hubble's law

Observation that the farther away a galaxy is, the faster is is moving away from us

Scientists have introduced the concept of dark energy to explain the

Rate of growth of the universe

According to the big bang theory

The universe began with an enormous explosion

Ordinary matter

less than half of the total matter in the universe