Download THE BIG BANG THEORY

THE BIG BANG THEORY
HOW IT ALL BEGAN….
BEFORE THERE WAS A UNIVERSE, THERE WAS..
• One single, infinitesimally small, dense and hot
point
• Then, for reasons that are unknown, that point,
expanded with energy that is unfathomable
• Time and Space began with this event
Universe started from a single point, and has
been expanding ever since
Expansion happened approx. 13.75 billion
years ago
Expansion contained all of the ENERGY in
space
NOT A “BIG BANG” NOT AN EXPLOSION!
• the matter is all actually standing still while
space itself expands dragging the matter with it
HOW DO WE KNOW IT STARTED FROM A SINGLE
POINT?
• Objects are currently moving away from each other today,
then, they must have been closer together yesterday, and the
day before that and so on…
THE FURTHER GALAXIES ARE AWAY FROM
EARTH, THE FASTER THEY ARE MOVING AWAY
• Known as Hubbles law
• Therefore, the closer these galaxies were to time
of the big bang
• So, information from these galaxies gives us
knowledge about the beginning of time!
AS THE UNIVERSE EXPANDS, IT COOLS
Universe has cooled from 1032 degrees to 3 degrees Kelvin in 15 billion years (K = C+273)
AS THE UNIVERSE EXPANDED, IT COOLED
• Energy that was released from cooling formed matter.
(Matter and energy are related, E=mc 2)
• The universe expanded, cooled then formed matter.
WHAT TRIGGERED THE BIG BANG?
• Scientists disagree on what started the big bang:
• Was it the edge of another expanding universe?
• What it radiation from another big bang hitting the tiny spot
that triggered it?
• Was it the result of radiation from a supernova?
• No one, as of yet, knows for sure
IF WE DON’T KNOW WHAT CAUSED THE BIG
BANG, DOES THAT MEAN THE THEORY IS NOT
VALID?
• Theories don’t try to explain everything, just what
evidence is available and pertinent
• the theory of Gravity doesn’t explain where mass
came from
• The Germ theory of disease transmission doesn’t
explain where germs came from
• Atomic theory doesn’t state where atoms come from
LESSON CHECK
• On a separate piece of paper, do the following:
• Describe how the universe was prior to the big bang
• Describe why galaxies that are further away from
Earth are moving faster than Earth
• Describe the universe today
CREATE YOUR OWN…
BIG BANG
EVIDENCE FOR THE BIG BANG THEORY
• Red Shift of GALAXIES
• Radiation left over from the Big Bang
• Composition of matter in the universe
REMEMBER THE EM SPECTRUM???
• a process in which photons (energy packets) travel
• do not need to travel through a medium
• All types of waves travel at the speed of light
RED SHIFT
AS AN OBJECT MOVES AWAY, THE WAVELENGTH
IT EMITS LENGTHENS
DOPPLER EFFECT
WHAT HAPPENS TO THE WAVELENGTH (COLOR)
AS OBJECTS MOVE AWAY? (LOOKING ONLY AT THE
VISIBLE PORTION OF THE SPECTRUM)
RED SHIFT
The electromagnetic radiation emitted by a moving object also exhibits the
Doppler effect.
•Redshift, a phenomenon of electromagnetic waves such as light in
which spectral lines are shifted to the red end of the spectrum.
RED SHIFT
Object moving closer light waves pushed together 
wavelength shorter appears blue
Object moving away light waves stretched out longer
wavelength  appears red
What color do you think galaxies appear from earth?
Object moving away, appears RED
Object
moving
towards,
appears
BLUE
RED SHIFT OF GALAXIES
• Astronomers observe galaxies are all red shifted from
Earth – What does this say about the galaxies in
relation to Earth?
• Therefore, all galaxies are moving away from earth
• Therefore, the universe is expanding
WAIT A MINUTE!! WHAT IS A GALAXY!?!
• a massive, system consisting of stars, stellar remnants, gas
and dust and dark matter (more on dark matter later!)
• Examples of galaxies range from dwarfs with as few as ten
million (107) stars, to giants with one hundred trillion (1014)
stars, each orbiting their galaxy's own center of mass
• Galaxies are held together by gravity
• Supermassive black holes reside at the center of most
galaxies.
THE ANDROMEDA GALAXY – OUR CLOSEST
NEIGHBOR – 2.5 MILLION LIGHTS YEAR AWAY
A VIEW OF 15% OF THE GALAXIES – THAT’S 3
MILLION GALAXIES REDSHIFTED
LESSON CHECK
• Take 3 minutes to discuss with your table partner
how the red shift of galaxies can be used as
evidence to support the theory of the big bang
COSMIC BACKGROUND MICROWAVE RADIATION
• 1964 by Penzias and Wilson
• a faint background glow, almost exactly the same in all
directions, that is not associated with any star, galaxy, or
other object
COSMIC MICROWAVE BACKGROUND RADIATION
 Radiation believed to be left over from the Big Bang
WHERE DOES THIS RADIATION COME FROM?
• As the universe expands, the space between the
photons that the expansion created grows
• As the space between the photons continues to
grow, the wavelength of those photons also
increases.
• This wavelength is in the microwave range (.051cm)
IMAGE FROM WMAP
SOUND OF COSMIC BACKGROUND RADIATION
http://Sound of Cosmic Radiation
Evidence of the big bang
Cosmic Background Microwave Radiation
LESSON CHECK
• Take 3 minutes to discuss with your table partner
how cosmic background microwave radiation
can be used as evidence to support the theory of
the big bang
EVIDENCE - TAKING A CLOSER LOOK
redshift slinky lab
COMPOSITION OF MATTER IN THE UNIVERSE
• Helium
• Deuterium (H-2, an isotope of hydrogen)
HELIUM IN THE UNIVERSE
• By observing ultraviolet light, astronomers found helium
in the early Universe.
• Helium forms when deuterium fuses with another
deuterium (H-2 and H-2 forming Helium)  for this to
happen, it must be super HOT! (around 10 billion
Kelvin)
BIG BANG NUCLEOSYNTHESIS – H-2 FUSING TO
FORM HELIUM
HELIUM – FROM FUSION IN STARS
• Helium is formed in the core of stars during fusion
• The fusion reaction releases energy in the form of
photons
• Stars and hydrogen bombs are the only things we know
of that make helium in the today’s universe.
HELIUM MADE DURING STAR FORMATION
• 1960: spectroscopic studies of stars showed that the
helium accounted for 20-30% of the mass of stars, the
rest (70-80%) being mostly hydrogen.
• However, 24% of the matter in the entire universe is due
to Helium…star formation of Helium couldn’t account for
all that Helium!
• Some, if not most, of the helium must have existed before
star formation.
HELIUM WAS MADE DURING THE BIG BANG
• physicists calculated that roughly 1/4 of mass was
converted into helium during the big bang, while the
rest remained as hydrogen.
• 1970s: spectroscopic studies of other galaxies have
confirmed that the majority of the observed helium did
exist before any star formation.
DEUTERIUM IN THE UNIVERSE
• 1973: studies of absorption spectra of
nearby stars showed that interstellar
medium (material between stars) contains
deuterium.
DEUTERIUM – AN ISOTOPE OF HYDROGEN H-2
• Deuterium, unlike helium, is not produced in stars at
all.
• In stars, deuterium quickly fuses to make Helium
• At temperatures above about one million degrees K,
deuterium breaks down into protons and neutrons.
• Astronomers in the early 1970s realized that no
known process in the present universe could have
produced deuterium.
DEUTERIUM IN THE UNIVERSE
• At the time of the big bang, temperatures
and densities were lowered so quickly,
there would have been no time for the
deuterium to break down, so the deuterium
present to day could have only formed
during the big bang.
HELIUM AND DEUTERIUM
• the abundance of helium and existence
of deuterium provide strong evidence
that the universe began with a hot,
violent expansion consistent with the
big bang model.
THE MYSTERY OF DARK MATTER – THIS IS NOT
ORDINARY MATTER!
• Today astronomers believe that around three quarters of the
mass of the Universe consists of dark matter, a substance quite
different from the ordinary matter that makes up atoms and the
familiar world around us.
• Dark matter only interacts with gravity, which means it neither
reflects, emits or obstructs light (or indeed any other type of
electromagnetic radiation). Because of this, it cannot be
observed directly.
• Dark matter remains a mystery today!
THE BIGGER MYSTERY: DARK ENERGY
• Hubble studies of the expansion rate of the Universe have found
that the expansion is actually speeding up.
• Astronomers have explained this using the theory of dark
energy, as a sort of negative gravity that pushes the Universe
apart ever faster.
• Dark energy is an even bigger mystery than dark matter!
LESSON CHECK
• Take 3 minutes to discuss with your table partner
how the composition of the universe can be
used as evidence to support the theory of the big
bang
READING ASSIGNMENT: FLEX BOOK: CHAPTER
1 AND 2
THE ORIGIN OF THE SOLAR SYSTEM
- THE NEBULAR THEORY
Collapsing Clouds of Gas and Dust
•1 billion years after the Big Bang
•Clouds of gases (Helium and Hydrogen) and dust begin to
clump together and collapse – called a NEBULA
CLOUD BEGINS TO CONTRACT…
• Force of gravity is greater than gas pressure, so
cloud begins to contract
• The cloud is initially spinning slowly.
• Due to angular momentum, the cloud spins faster as
it contracts.
THE SPINNING NEBULA FLATTENS…
• Force of gravity, gas pressure and rotation
CONDENSATION OF PROTOSUN AND
PROTOPLANETS
• Instabilities in collapsing rotation cloud cause local
regions to contract. (Due to gravity)
• Protosuns and protoplanets become the sun and
planets in our solar system
CENTRAL BULGE CONTINUES TO COLLAPSE
• Gravity causes bulge to continue to collapse
• Temperatures inside bulge get extremely hot – several
million degrees
• Hydrogen begins to fuse to form helium which releases
enormous amounts of energy  a star (our sun) is born
NEBULAR HYPOTHESIS OF SOLAR SYSTEM
FORMATION.
From start to finish, it
took something like 10
million years to form
the sun and planets
from a collapsing
cloud of gas, and this
is not very long at all!!
HUBBLE SPACE
TELESCOPE PICS
THE MILKY WAY GALAXY
THE MILKY WAY GALAXY
THE FATE OF THE MILKY WAY
READING ASSIGNMENT: FLEX BOOK: CHAPTER 3
READING ASSIGNMENT: FLEX BOOK: CHAPTER 4
OUR SOLAR SYSTEM
AGENDA
•
Where is our solar system
•
Characteristics of the planets in our solar system
SOLAR SYSTEM
The Sun
•
•
Eight Planets
•
One dwarf planet
•
Sixty-one satellites of the planets
•
Many Comets and asteroids
NORM HERR (SAMPLE FILE)
11/15/99
SUN
• 75% hydrogen and 25% helium by mass
• Sun converts hydrogen to helium in its core
• Differential rotation
• equator the surface rotates once every 25.4 days
• near the poles it's as much as 36 days
• Core conditions
• temperature is 15.6 million Kelvin
• pressure is 250 billion atmospheres
NORM HERR (SAMPLE FILE)
11/15/99
MERCURY
•
Orbit
• highly eccentric
• perihelion 46 million km
• aphelion it is 70 million km
•
One full day-night cycle takes 179 earth days
•
Temperatures vary from -173 C – 427 C
NORM HERR (SAMPLE FILE)
11/15/99
VENUS
•
Volcanism
•
Rotates backwards
•
Dense Atmosphere
•
Hot – 480 C
•
90x atmospheric pressure compared to Earth
NORM HERR (SAMPLE FILE)
11/15/99
EARTH
•
Moon is 1/6 mass of earth
•
period of rotation: 24 hours
•
period of orbit 365.25 days
NORM HERR (SAMPLE FILE)
11/15/99
MARS
•
Solid carbon dioxide is found at the poles
•
Mars is known as the Red Planet
•
½ the size of Earth
NORM HERR (SAMPLE FILE)
11/15/99
ASTEROID BELT
•
Contains lumps of rocks and metal
•
Several million asteroids
JUPITER
•
Largest Planet - Jupiter contains over 70% of the mass in the solar system
outside the Sun
•
It is about 11 times the radius and 330 times the mass of the earth.
•
Jupiter is not a solid body, but instead is a ball of gas and liquid (mostly
hydrogen and helium)

Great Red Spot

63 Moons

Takes 12 years to rotate around the Sun
SATURN
• Gas giant.
• Strong surface winds (1500 mile/hour).
• Less dense than water.
• Has rings made up of ice, dust and rocks
• 29 years to rotate one time around the Sun
• Atmosphere is Helium
• Has 60 moons – Titan is its largest (larger than Mercury)
NORM HERR (SAMPLE FILE)
11/15/99
URANUS
•
Rolls on its axis, doesn’t spin
•
Methane Atmosphere
NORM HERR (SAMPLE FILE)
11/15/99
NEPTUNE
•
Wind speeds of 1000km/hour
•
Ice Volcanoes
Note the apparent storms
NORM HERR (SAMPLE FILE)
11/15/99
PLUTO
•
Pluto is a ‘dwarf planet’
•
1/5 the mass of Earth’s Moon
•
Orbit is inclined 17deg to the ecliptic, so it goes farther above and below the plane than of
the other planets
HOW CAN WE REMEMBER THE ORDER OF THE
PLANETS?
•
My Very Educated Mother Just Served Us Nine Pizzas
•
More?