Bell Work9/8/2011 Chapter 2 in the Oceanography textbook is
entitled Origins. What might we be studying the origins of in this
chapter? Oceans Solar System Earth Moon Universe Atmosphere Slide 2
Origins Oceanography Chapter 2 Slide 3 Part 1: Origin of Universe
& Galaxies Slide 4 Big Bang Theory Event that occurred
approximately 14 billion years ago.Event that occurred
approximately 14 billion years ago. All mass & energy was
concentrated at a geometric point.All mass & energy was
concentrated at a geometric point. The Big Bang marks the beginning
of space and time.The Big Bang marks the beginning of space and
time. Slide 5 Evidence Supporting the Big Bang Theory 1.Expansion
of the universe. 2.Cosmic Background Radiation. 3.Nucleosynthesis
of light elements. 4.Formation of galaxies. Slide 6
ELECTRO-MAGNETIC SPECTRUM Smallest wavelengthLargest wavelength
What we see with our eyes Slide 7 Looking at the Crab Nebula with
the EM Spectrum UV IR RADIO MW X-RAY VISIBLE Slide 8 Expansion of
Universe Red Shifted = moving away Blue Shifted = moving towards
90% of all stars & galaxies observed are moving away from the
Milky Way Slide 9 Cosmic Background Radiation Ancient universe had
small variations in temperature. Over 14 billion years, gravity
magnified these small differences into clusters of galaxies today.
A sky map of cosmic background radiation (microwave) taken by NASAs
satellite called COBE. Slide 10 Scale & Structure in Universe
Universe is composed of voids and galaxy clusters. Voids could be
millions of light years across. Slide 11 Slide 12 Nucleosynthesis
of Light Elements Hydrogen atoms: the most common form of matter in
the universe. Atoms have mass. Clump together under gravity.
Formation of elements: He through Fe (iron) inside stars (nuclear
fusion) Heavier elements in super- nova explosion (Fe & beyond)
Slide 13 Formation of Large-Scale Structures Galaxies, like our
Milky Way, are composed of stars, dust, gas and debris held
together by gravity. Slide 14 Galaxies The Milky Way is approx.
100,000 light years in diameter. Our solar system is located on an
outer spiral arm 27,000 light years from the galactic bulge. A
black hole may be found within the bulge of the galaxy. Slide 15
Types of Galaxies Spiral Galaxy Irregular Galaxy Elliptical Galaxy
(globular cluster) Slide 16 More Types of Galaxies Slide 17 Part 2:
Origin Stars (Life Cycle of a Star) Slide 18 Life Cycle of a Star
Slide 19 Nebulae are clouds of dust & gas within galaxies.
Nebulae are concentrated in the arms of spiral galaxies. Step 1:
All stars are born in nebulae. Slide 20 Types of Nebulae Supernova
Nebula Dark Nebula Slide 21 Slide 22 Slide 23 Proto-stars
Proto-stars grow as hydrogen & helium gas are pulled together
by gravity. Proto-stars are not hot enough for fusion to occur.
Artists rendition of a protostar Slide 24 As material continues to
collect, the protostar gets hotter and hotter and hotter
until...... Nuclear fusion begins and blows off the remaining gas
(our first atmosphere)! Gamma & X- rays Slide 25 Stage 2: Main
Sequence Star Our sun is a main sequence star (stable). It is a
yellow dwarf star. Nuclear fusion of hydrogen gas into helium gas
powers our Sun. Slide 26 Equation of Fusion 4 H + 2e- 1 He + 2 +
photons This is the nuclear reaction that happens inside stars and
gives off massive radiation. All elements up to iron form inside
stars, the remaining elements form during a supernova explosion. e
= mc 2 Slide 27 Bell Work9-11-12 What event in a stars life cycle
changes a proto-star into a main sequence star? Nuclear Fusion
occurs when the core temperature = 10 million degrees Kelvin Slide
28 Stage 3: Red Giant Stage Hydrogen in the core is used up and
fusion no longer balances gravity. Star expands and collapses.
Gravity wins! Slide 29 Slide 30 Slide 31 Red Giant Stage - Unstable
Slide 32 Stage 4 Nova Stage Slide 33 Slide 34 Slide 35 Stage 5:
White Dwarf Stage All fuel is used up. Dim, faint with high
temperature. Some Sun-like stars become white dwarfs made of
carbon. Some white-dwarfs flare up to a nova. Slide 36 Bell
Work9-12-12 Where do the following elements form? Hydrogen...
Helium to iron... Elements heavier than iron... Big Bang Inside
stars Supernova explosion Slide 37 Types of Stars Cool & Bright
Cool & Dim Hot & Bright Hot & Dim Our sun Dying stars
Dead stars HR Diagram Slide 38 Bell Work9-13-12 Besides having life
and abundant liquid water, what makes Earth different from the
other terrestrial planets? Large moon Magnetic field High Density
Plate Tectonics (volcanoes) Slide 39 Part 3: Origin of the Solar
System Slide 40 Condensation Theory The condensation theory
explains how stars & planets are believed to be formed.
Condensation theory is based on the observation of stars and
planets at different stages of development. Scientists have
inferred a sequence in which these stages occur. Slide 41 Origin of
Our Solar System Metals (Fe, Mg, Al, Mn) & Rock (Si, K, Ca)
high melting points Gases like methane (CH 4 ) and ammonia and
solids like ice low melting points 5 billion years ago: A solar
nebula + shock wave & heavy atoms from a supernova= formation
of solar system. Slide 42 Formation of Planets New planets formed
by a process called accretion, the clumping of small particles into
large masses. Accretion lasted about 30 to 50 million years. As the
sun began nuclear fusion, solar radiation swept past the inner
planets clearing excess particles and stopping the accretion
process. Planet formation Terrestrial planets Gas planets Slide 43
Our Solar System Eight planets, asteroid belt, and icy bodies
revolve around a star (our sun) in a plane. Planet composition:
Inner 4 planets are terrestrial (rock/metal) Outer 4 are gas giants
(gas/ice) Beyond Neptune are icy bodies (including Pluto) and
asteroids. Slide 44 Slide 45 Terrestrial Planets Mercury is a
small, hot planet made mostly of iron. Terrestrial planets are
small, dense, and composed of rock. Venus is the hottest planet in
the solar system due to run- away greenhouse effect. Slide 46 More
Terrestrial Planets Terrestrial planets have few or no moons and no
rings. Mars is a dead planet with little atmosphere & evidence
of liquid water on its surface. Slide 47 Gas Planets Gas Planets
are large, with low density, and composed of methane & ammonia
gas. Slide 48 More Gas Planets Gas planets have lots of moons,
rings, and no craters. Uranus & Neptune get their blue color
from methane gas. Slide 49 Moons of Gas Planets Europa Slide 50
Moons of Gas Planets Lakes of liquid methane Titan Slide 51 Bell
Work8-27-13 What process was responsible for planet building?
Accretion!! Slide 52 Part 4: Origin of the Earth, Atmosphere &
Oceans Slide 53 Formation of Earths Crust 4.6 billion years ago
Earths crust was partially melted by: asteroid impacts
gravitational compression decay of radioactive elements Moon
Formation Moons importance!! Added large amount of material &
radioactive heat to Earths mass. Kept our core molten = magnetic
field. Slide 54 Formation of Earths Crust Layered or stratified
Earth Density stratification of the Earth: dense material like iron
& nickel sank to form the core light material like silicates
(SiO 2 ) magnesium, and aluminum forming the crust. Also called the
Iron Catastrophe Rocky crust Fe & Ni core Slide 55 Formation of
the Ancient Atmosphere Earth's interior was heated primarily from
decay of radioactive elements causing volcanism. Volcanic eruptions
spewed gases from Earth's interior into the atmosphere, a process
called out-gassing. Most of the gas was carbon dioxide and water
vapor. CO 2 H2OH2O SO 2 Burp!! Slide 56 Formation of Modern
Atmosphere About 3.5 billion years ago the primitive atmosphere
changed: CO 2 dissolved into young ocean to form carbonic acid
& combining with crustal rocks. Slide 57 Oxygen Revolution 2
billion years ago Earths first ever revolution!! Oxygen began to
accumulate in the atmosphere with the evolution of plants!! Burp O
2 ! Stromatalites blue-green algae AncientModern Slide 58 Formation
of Ocean Floor Two types of Earths crust: Ocean Crust (basalt)
Continental Crust (granite) Ocean crust is more dense and thinner.
The tectonic processes formed the sea floor. Slide 59 Formation of
the Ocean Forming about 4.2 billion years ago, the oceans water
originated from: Volcanic out-gassing continued until the
atmosphere contained ~40% water vapor. Additional water may have
come from comets. Earth cooled, water condensed and formed the
oceans. Out-gassing continues today. Volcanic out-gassing from
volcanically active areas like Yellowstone & Mammoth Lakes
