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The Universe

Helpful cards for the Universe test in Astronomy :)

The Planck Era is also known as the... Grand Unified Theory Era
During the Quark Era, the continually forming particles/antiparticles looked something like.. Particle Soup
Physics are as they are today beginning in which Era? Quark Era
What is quark confinement and in which era did it happen? When quarks and antiquarks combine in 2's and 3's, in the Hadron Era
What were numerous in the Lepton Era? Electrons, Neutrinos, and their antiparticles.
Why is the Opaque Era called this? because there was an ocean of matter particles that were in a continual state of interaction with protons, making the universe appear "foggy."
Our present era is the Matter Era
Electrons were bound to atoms until.. the first stars formed, reheating matter
What is Superforce? force that originally came from the Big Bang, divided into Grand Unified Force and gravitational force, then GUF split into strong nuclear force and electroweak force, and finally electroweak force divided into weak nuclear force and electromagnetic force
What are the 5 things that support the Big Bang Theory? Cosmic Background Radiation, Expansion, Balance of the Elements, General Relativity, and the Dark Night Sky
When did the first stars begin to form, ending the "Dark Ages"? 200 million years after the Big Bang
How large were the first stars? 100-1000 times the mass of the sun
What are hypernovae? The death of the first massive stars
How were elements heavier than iron formed? deaths of the first massive stars, which were essential for the formation of everything
When did the first galaxies begin to form? 500 million years after the Big Bang
What was the chemical composition of the universe before stars? 76% Hydrogen, 24% Helium, Trace of Lithium
What are the four different types of galaxies? Irregular, Elliptical, Spiral, and Lenticuilar
What are irregular galaxies? clouds of stars that lack clear disk or ellipse like structure
What are elliptical galaxies? balls of stars from perfect spheres through eggg shapes to cigar shaped ellipsoids
What are spiral galaxies? vast, rotating disks of stars, dust and gas. They have a ball shaped nucleus inside a disk with spiral arms.
What are lenticular galaxies? similar to spiral, have a nucleus of red and yellow stars, shaped like a lens.
Created by: erinmarine