With a partner on page
55 create a definition for
what is a:
Theory
Write 2 examples
Click here for video flow chart
Scientific Theory
•
A scientific theory is an explanation of some
aspect of the natural world, based on a body
of facts that have been repeatedly confirmed
through observation and experiment. Such
fact-supported theories are not "guesses" but
reliable descriptions of the real world.
Formation of the
Universe
The Big Bang Theory
(BBT)
Red Shift
Shift of wavelengths of light towards
the red end of the spectrum; happens
as a light source moves away from us
(Earth).
Red shift is related to the Doppler
Effect:
Change in frequency of a wave for
an observer moving relative to its
sourceclick for video
Red Shift Visual
Hubble’s Law
The farther away a
galaxy is, the faster it is
moving away from us.
Used Red Shift data to
come to this
conclusion.
Expanding Universe
What’s the Big Deal!?
- If we study this expansion we can
determine:
~How the universe formed
~Age of universe
~Could support idea of galaxy
formation; material stayed in clumps
then pulled together over time
Expanding Universe Visual
Extra Help
https://www.khanacademy.
org/science/cosmologyand-astronomy/universescale-topic/big-bangexpansion-topic/v/red-shift
Doppler Effect
See how the wavelength is compressed due
to movement of the car.
This works similarly with light as it moves
away from Earth.
Background Radiation
Background Radiation
Called Cosmic Microwave
Background Radiation (CMB)
‘Left over’ thermal radiation from Big
Bang
This has been observed and is nearly
uniform throughout the entire
universe
CMB Visual
CMB Radiation
CMB so uniform it is nearly
impossible to explain where else it
could have come from
By studying CMB we have identified
the Universe to be about 13.7 billion
years old
Evidence for BBT
Red Shift
Expansion of the Universe
CMB
Uniform radiation
throughout the Universe
Review-- Write In Notebook
1. How did Hubble determine that
the universe is expanding?
2. How do astronomers determine
the composition of distant stars?
3. What is the significance of the
idea that the universe is
expanding?
Big Bang Balloon Activity
Title : Big Bang Balloon Activity
Purpose: To model the
expansion of the universe over
time
Procedure: See Handout
Big Bang Balloon Activity
Data Table:
Distance from Home Galaxy over time
Galaxy
Time 1 Time 2 Time 3 Time 4 Time 5
Home
Galaxy
Galaxy A
Galaxy B
Galaxy C
Galaxy D
Galaxy E
Big Bang Balloon Activity
Conclusion: answer the following questions in your
notebook, under the heading “Conclusion.”
•
Be sure to use complete sentences.
•
1. How did the distance from the home
dot to each of the other galaxies change
each time you inflated the balloon?
•
2. Did the galaxies near home or those
farther away appear to move the
greatest distance?
Big Bang Balloon Activity
Conclusion: answer the following questions in your
notebook, under the heading “Conclusion.”
•
Be sure to use complete sentences.
•
3. How does this activity help to explain
how the big bang could have happened?
•
4. How could you use this model to
simulate the “Big Crunch” a time when
all the galaxies might collapse in on
themselves? What would you do to your
balloon?