Lecture 2: Origin Of The Universe Flashcards
Describe the properties of the universe.
Dust/clouds
Stars
Remnants of stars and galaxies
Describe the structure of the universe.
Earth, solar system, Milky Way galaxy, local group, local supercluster, Virgo
What is the evidence for the universe having a definite beginning?
Universe extends beyond our galaxy, same composition hydrogen and helium, universe is expanding
How old is the universe?
Approximately 13.7 billion years old
What is the big bang theory?
All energy and matter of the universe existed in a hot dense state which exploded and has continue to expand call and evolve
How has the universe evolved since the Big Bang?
The universe has continued to expand
What is electro magnetic radiation?
The transfer of energy through space by electromagnetic waves.
Which has the shortest wavelength’s?
Gamma
Which have the longest wavelength’s?
Radio
What form of radiation do we see?
Visible light
What is spectroscopy?
The study of the properties of light.
What is spectroscopy dependent on?
Wavelength dependent.
What is a spectrum?
Light pattern produced by passing light through a prism
Describe the Doppler effect
Apparent change in wavelength of radiation do to the relative motion of a source and an observer
Describe the Doppler affect his application in astronomy
Red/blue shift describes how light changes as objects in space move closer or further away from us
What does a red shift mean?
Moving away from us. Black lines move into red wavelength
What does a blueshift mean?
Moving towards us. Black lines move into blue wave length
What did the Doppler effect reveal about the universe?
most galaxies have read shifts, and relative velocity is of moving objects
How is the amount of shift of a galaxy related to the velocity?
How fast or slow it is moving
What is the conclusion of the Doppler effect?
The universe is expanding
What are the two theories on how the universe may end?
Closed universe (Big Crunch), open universe
