[ASTRONOMY] Unit 9 REVIEW: Doppler, Redshift, CBR (SadRebelMom)

George Smoot and John Mather

Used data on CMB from COBE satellite; won Nobel Prize for Physics

Fred Hoyle

Updated the Steady State Model to include expansion of universe along edges; coined term "Big Bang Theory"

Edwin Hubble

research proved universe still expanding;

showed that galaxies exhibit a redshift which means they are moving away from us

Georges Lamaitre

First to propose that the Universe started from a small "primeval atom" state that began expanding

Penzias and Wilson

Accidentally discovered the cosmic microwave background radiation using a large microwave telescope

Christian Doppler

discovered the shift in wavelength and frequency perceived in sound and light when the source is moving toward or away from an observer

Big Bang Theory

The theory that the universe originated in a huge explosion that released all matter and energy.

Steady State Theory

the universe has always existed and always will, in the state it is in now

COBE

1st satellite built to study CMB; mapped background radiation which is the signal left from the big bang; Cosmic Background Explorer (1989 - 1993); information led to new field of science "Cosmology"

Isotropic

Measurements taken give same results in all directions

Anisotropic

having different properties in different directions

Early Helium Synthesis

In the natural order, Helium is preferred configuration when forming atoms vs. Hydrogen; helped to prove Big Bang Theory

protium, deuterium, tritium

3 isotopes of hydrogen (All have only 1 proton but Protium=0 neutrons; Deuterium=1 neutron; Tritium=2 neutrons)

Doppler effect

An observed change in the frequency of a wave when the source or observer is moving

Redshift

A Doppler shift in which spectral features are shifted to longer wavelengths, observed when an object is moving away from the observer. (HINT: car's tail lights)

Blueshift

the displacement of the spectrum to shorter wavelengths in the light coming from distant celestial objects moving toward the observer. (HINT: car's headlights)

Characteristics of Light

Wavelength, Frequency, Electric Field, Magnetic Field, Direction of movement, Transverse Wave; No medium required

Transverse Wave

A wave in which the particles move perpendicularly to the direction the wave is traveling; in light, these waves are electrical and magnetic

Speed of Light

3 x 10^8 m/s

Light Radiation Pressure

photons which can apply pressure to matter

Reasons BBT not accepted

1) religious origin theory in conflict; opposed by church

2) most scientists' research based off Steady State Model

3) preferred Ariostle's model

4) contradiction to Thermodynamics law where matter cannot be created or destroyed

Moving away from Earth

If top picture is from a laboratory, then in the bottom picture a galaxy is...

Bottom Picture

If both pictures are REDSHIFTED, then is the top or bottom picture refer to the galaxy moving faster away from Earth

Cosmic Background Radiation/CBR

radiation uniformly detected from every direction in space; considered a remnant of the big bang

Cosmic Microwave Background/CMB

radiation left over from the big bang