Big Bang & Universe
What is happening to the universe over time?
It is expanding.
What type of energy includes visible light and radio waves?
Electromagnetic radiation.
What force pulls matter together and helps form stars and galaxies?
Gravity.
What is the explosion of a star called?
A supernova.
What is the most widely accepted theory explaining how the universe began?
The Big Bang Theory.
What unit measures the distance light travels in one year?
A light-year.
What objects in space produce their own energy?
Stars.
What does gravity cause a cloud of gas and dust to do when a solar system begins forming?
Collapse inward.
According to the Big Bang Theory, the universe began as what?
A very small, hot, dense point.
If a star is 4 light-years away, how long does its light take to reach Earth?
4 years.
What happens in a star's core to produce its energy?
Nuclear reactions.
What shape does the collapsing cloud of gas and dust form as the solar system develops?
A disc.
Which scientist found evidence that the universe was expanding by studying light from distant galaxies?
Edwin Hubble.
What is the name for light shifting toward the red end of the spectrum as an object moves farther away?
Redshift.
What is a huge group of stars held together by gravity called?
A galaxy.
What star formed at the center of our solar system?
The Sun.
Which theory suggested that new matter formed as the universe expanded, keeping its density the same?
The steady state theory.
What dish-shaped instruments detect radio waves from space?
Radio telescopes
What are the vast clouds of gas and dust where stars form called?
Nebulae.
What two types of objects formed as gravity pulled together the remaining material in our solar system?
Planets and moons.