Composition of the Universe
What is dark matter?
a hypothetical substance that only interacts with gravity.
What is dark energy?
a mysterious force that appears to be causing the expansion of the universe to accelerate
About what percentage of the universe is composed of dark matter?
about 24%
About what percentage of the universe is composed of ordinary matter?
about 4-5%
About what percentage of the universe is composed of dark energy?
about 71%
What do most scientists believe dark matter is?
an unknown subatomic particle that does not reflect, emit, or obstruct light
What do scientists believe "fills the spaces" in the universe?
dark energy
Why is it important to understand the chemical composition of the universe?
it is key to understanding the processes that took place during the very early universe
What is considered "ordinary matter"?
matter made of protons, neutrons, and electrons. any matter that contains atoms.
What all does ordinary matter make up in the universe?
stars, planets, and galaxy clouds
