Module 5 Lesson 2 Flashcards
what is the big bang theory?
the big bang theory is the theory of how the universe began.
its the theory that the universe began at a small, dense and hot state. then soon it rapidly expanded. from which the universe is still expanding ever since
What evideince is there to the big bang theory?
Hydrogen is present throughout the universe
Galaxies are red-shifting, which supports the idea that space is expanding
cosmic backround radiation is the energy left over from the expansion of the universe, observed as dark energy.
What evideince is there to the big bang theory?
Hydrogen is present throughout the universe
Galaxies are red-shifting, which supports the idea that space is expanding
cosmic backround radiation is the energy left over from the expansion of the universe, observed as dark energy.
How did George Lemaitre contribute to the big bang?
georage lemaitre made the idea that the primeval atom came from infinitesimally dense
he made a constant called hubbles contant which gave evidence for the expansion of the universe
what can the spectra of an object tell us?
it can tell us the composition and the direction it is moving in
explain the doppler effect in terms of light.
light from a source that is moving closer will be a short wavelength which will make the light to appear blue.
while light form a source that’ss moving away will have a longer wave length which will cause the light to appear red
what is the doppler effect
the doppler effect is an increase or decrease in the frequency of sound, light or other waves.
additions to the theory (nI)
This suggests that the universe will become less and less dense until the temperature of the universe decreases to absolute zero
This temperature is where there is a complete absence of heat and energy
This also suggests that the expansion of the universe will slow down, then eventually reverse
This will cause a second explosion and a collapse
This has been called “The Big Crunch”
Recent research suggests that the universe is expanding at an accelerated rate
This wasn’t predicted in the original theory
Scientist have now added to the theory the presence of Dark Matter and Dark Energy to explain it
what is red-shifting and blue-shifting?
blue-shifting is when the spectral lines move closer to the blue side of the spectra. this indicates that the object is coming closer and has a short wave length (it has more energy)
while red-shifting is when spectral lines move closer to the red side of the spectra. this indicates that the object is moving away and a has a long wavelength (less energy)
(this is an example of the doppler effect)
how did Edwin hubble contribute to the big bang theory?
he provided evdience that we live in a expanding universe.
hubbles law alllowed atronomers to calculate how long ago galaxies started moving apart
how did george gamow contribute to the big bang theory?
gammow contributed by stating that the universe must have had a increadibly hot orgin.
what is cosmic microwave backround? and how is it evidence for the big bang theory?
cosmic microwave backround is leftover radiation from the big bang. this is evidence because it predicts that the early universe was a very hot place that expands.
how might we see cosmic backround radiation in our homes (not done)
we see cosmic backround radiation in our home when you turn on a tv and switch to a different channel you can see the cmb static signal on the screen. as it is an afterglow of the big bang
what do you think should be considered the ninth planet of our solar system? pluto? Planet nine? or neither? why do you think this should be the case?
I think neither should be considered the ninth planet.
for pluto it is not considered a planet because it is unable to clear orbit of debris which makes pluto not a planet.
for planet nine it is a “hypothetical planet.” which means we don’t know if planet nine actually exists. there is no proof of the planet actually existing so it cannot be considered the ninth planet.
what is planet 9?
planet 9 is a HYPOTHETICAL planet that is BELIVED to be in our solar system.
it is yet to be found but the features in the solar system suggest that it may exist
