A
A large assembly of stars, interstellar gas, and dust.
What are galaxies?
Roughly spherical galaxies.
What are elliptical galaxies?
Spiral-shaped galaxies.
What are spiral galaxies?
Galaxies that are any other shape.
What are irregular galaxies?
Galaxies that form new stars much faster.
What are starburst galaxies?
A group of galaxies.
What are clusters?
A group of neighboring clusters of galaxies.
What are superclusters?
It occurs when objects move away from us. It is also known as the “Doppler effect”.
What is a "redshift"?
At the beginning of the universe, it EXPLODED outward.
What is the Big Bang?
Microwave radiation fills all space in the observable universe, supporting the big bang theory.
What is cosmic background radiation?
Matter that we cannot see or touch causes rotation curves of galaxies, gravitational lensing, and the behavior of galaxy clusters.
What is dark matter?
If our universe is EXPANDING, something must pull on it from the OUTSIDE that OPPOSES GRAVITY.
What is dark energy?
The part of the universe that we can see from Earth.
What is the observable universe?
The gravitationally bound cluster of galaxies includes our Milky Way, Andromeda, Triangulum galaxies, and several smaller dwarf galaxies.
What is the local group?
A large structure in the universe that contains our Milky Way galaxy and many other galaxies.
What is the local supercluster?
A bright, compact region at the center of a galaxy that emits a significant amount of energy across the electromagnetic spectrum, powered by a supermassive black hole actively accreting matter
What is the active galactic nucleus?
The universe is _ years old.
13.8 billion.
The Milky Way galaxy is _ years old.
13.61 billion.
Adronoma is _ away from us.
2.5 million light years.
The universe's average temperature is _.
2.73 Kelvin.