1. The Big Bang!
This sample of the heavens is “considered representative of the typical distribution of galaxies in space, because the universe, statistically, looks largely the same in all directions. Gazing into this small field, Hubble uncovered a bewildering assortment of at least 1,500 galaxies at various stages of evolution.”

2. Olber’s Paradox
In 1826, the astronomer Heinrich Olber’s asked, "Why is the sky dark at night?" By his time, physicists had learned enough to realize that, in a stable, infinite universe with an even distribution of stars, the entire universe should gradually heat up.
Prior to this, many believed the universe simply had existed for all time – a steady state model of the universe.
Source:

3. An Expanding Universe The beginnings of the theory…
Edwin Hubble – Astronomer
1923 Proves that the universe extends far beyond the edges of the Milky Way galaxy
Notices that galaxies are “red-shifted” – moving away from us

4. An Expanding Universe Hubble's Law:
The farther away a galaxy is from Earth, the faster it is moving away.
Note the use of the term “law” here – this is still only theoretical, but it has become dogma in cosmology.

5. The Big Bang Theory
Where do cosmologists get the idea that the universe originated in a Big Bang?
Expanding Universe
Redshift
Cooling Cosmos
Cosmic Microwave Background Radiation
Abundance of Light Elements
Hydrogen, Helium, and Lithium

7. The Big Bang Theory
Where do cosmologists get the idea that the universe originated in a Big Bang?
Expanding Universe
Redshift
Cooling Cosmos
Cosmic Microwave Background Radiation
Abundance of Light Elements
Hydrogen, Helium, and Lithium

8. An Expanding Universe - Redshift
Source: image:

9. Raisin Bread Dough Analogy
Makes no sense without caption in book

11. An Expanding Universe
In 1948, Russian-born physicist George Gamow took the next step by realizing that if all the galaxies are flying apart at high speed, the entire universe must have been concentrated in a single point at some time in the past.
Let’s review:
Hubble observed that there existed galaxies in the universe besides our own
Hubble began measuring the amount of spectral red-shift in the light observed from those distant galaxies or nebulae
Hubble correlated the relationship between distance and red-shift
This was then determined to be similar to the Doppler Effect and implied the observed objects were moving away from the viewer.
This then led others to hypothesize that if distant objects were all moving away from us, the universe must be expanding.
Gamow proposed that if galaxies are moving away from one another now, they must have been concentrated in a single point at some time in the past.
Thus, we have the origin of the Big Bang Theory.
Source: Image:

12. Reverse Time
The Primordial Atom

13. An Expanding Universe
During a radio interview, scientist, Fred Hoyle, coined the name "Big Bang“ – some say Hoyle was making fun of the theory, he claims he was only trying to explain how it was different than his own “steady state” theory.
… but the term became popular, and has prevailed to the present day.
Let’s review:
Hubble observed that there existed galaxies in the universe besides our own
Hubble began measuring the amount of spectral red-shift in the light observed from those distant galaxies or nebulae
Hubble correlated the relationship between distance and red-shift
This was then determined to be similar to the Doppler Effect and implied the observed objects were moving away from the viewer.
This then led others to hypothesize that if distant objects were all moving away from us, the universe must be expanding.
Gamow proposed that if galaxies are moving away from one another now, they must have been concentrated in a single point at some time in the past.
Thus, we have the origin of the Big Bang Theory.
Source: Image:

15. The Big Bang Theory
Where do cosmologists get the idea that the universe originated in a Big Bang?
Expanding Universe
Redshift
Cooling Cosmos
Cosmic Microwave Background Radiation
Abundance of Light Elements
Hydrogen, Helium, and Lithium

16. A Cooling Cosmos - CMB Cosmic Microwave Background Radiation (CMBR)
NASA projects
COBE (Cosmic Background Explorer)
WMAP (Wilkinson Microwave Anisotropy Probe)
Source:

18. A Cooling Cosmos - CMBR
1992 COBE took a “picture” of the entire universe and its cosmic microwave background radiation
In February 2003, the WMAP data showed much greater detail
Source:

19. A Cooling Cosmos - CMB
As the electromagnetic wavelength is lengthened (stretched out by an expanding universe), gamma rays from the earliest stages of the big bang would turn to X-rays, UV, visible light, IR, and ultimately microwave
Source:

20. The Big Bang Theory
Where do cosmologists get the idea that the universe originated in a Big Bang?
Expanding Universe
Redshift
Cooling Cosmos
Cosmic Microwave Background Radiation
Abundance of Light Elements
Hydrogen, Helium, and Lithium

21. Hydrogen, Helium, and Lithium are only elements assumed to be produced directly from Big Bang, all others are synthesized in stars
Elements heavier than Iron (Fe) are produced in the outer envelopes of super-giant stars and in the explosion of a supernova
1. Only three elements could have formed out of the Big Bang itself: H, He, Li
2. All heavier elements up to Iron (Fe) – see red lines – are assumed to be formed through nuclear fusion within stars and then ultimately released into the universe when stars “burn out” and supernova
3. Elements heavier than Iron (27+ on the periodic table) are all created in the explosion of stars (supernova)

23. How the Universe was formed…
The Big Bang
How the Universe was formed…

24. A quick review of the life-cycle of stars…
Makes no sense without caption in book

25. BIG BANG Beginning of light Nebula Star Planetary Nebula
Elements #4 through 26
Beryllium Oxygen
Boron Sodium
Carbon Aluminum
Nitrogen Argon
Nebula
Primordial Atom .
Gravity & Nuclear Fusion
Nuclear Fusion
Gravity
Star
quarks, electrons, protons, neutrons
Death
Gravity
Nuclear Fusion
Planetary Nebula
Planetary Nebula
Gravity
Gravity
Star
cooling
Super-Giant
ATOMS
Hydrogen
Helium
Lithium
Gravity
Elements #27 and higher
Nickel Zinc
Copper Lead
Xenon Gold
Silver Cadmium
Death
Nuclear Fusion
Gravity
Planets
Super Nova

26. Universe is 75% Hydrogen, 25% Helium Planets, Solar Systems, TODAY
How long did it take?
BIG
BANG
1 to 3 seconds
Universe is 75% Hydrogen, 25% Helium
1st Hydrogen Atoms
3 minutes
200 million yrs.
13.7 billion years
Planets, Solar Systems, TODAY
nebulas, stars
Larger Elements
black-holes, galaxies

27. Cosmic Background Radiation
“Dark” Matter & Energy
Scientist think that the universe is made up of much more “stuff” than we can detect. The “ripples” indicate there must be more than we can see…
Cosmic Background Radiation

28. Composition of the Universe
The Cosmic Background Radiation shows us that only 4% of the universe is made of “stuff” we can see.
4% Atoms
23% Dark Matter
73% Dark Energy

30. “Dark” Energy
According to Newton’s 1st law – an object in motion, remains in motion, at a constant speed and direction
Per Hubble’s law, galaxies in the universe are NOT moving at a constant motion, they are accelerating
Therefore, there must be some “Dark Energy” that is pushing galaxies apart – working the opposite of gravity

31. Inertia (Newton’s 1st Law) explains the top galaxy’s motion – constant speed, straight line.
Dark Energy is a theoretical explanation for the second galaxy's movement - acceleration.