Probing the Edge of the Solar System: Formation of an Unstable Jet-Sheet

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Stellar Astrophysics An Introduction Aug. 28,
2012
ASTR730 / CSI661 Fall 2012 Jie Zhang
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The Big Bang
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1920.jpg
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History of the Universe
http//www.negotiationlawblog.com/Big20Bang.jpg
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Physical Forces
Depending on temperature (T) and density (?)
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Inflation

• Inflation occurs at 10-35 second after the Big
  Bang when temperature of universe dropped to 1027
  K at this temperature, strong force became
  distinct from the electromagnetic-weak force
• Before the inflation, the space is empty,
  filled with only virtual particles dictated by
  quantum mechanics
• Matter and energy of the universe is created
  during the inflation
• Just after the inflationary epoch, the universe
  was filled with particles, antiparticles and
  energetic gamma-ray photons

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Create Radiation

• At t10-6 second, the temperature in the universe
  dropped to the threshold temperature of 1013 K,
  at which the photons can not produce proton and
  anti-proton pairs (and neutron and anti-neutron
  pairs)
• At about t 1 second, temperature fell below 6 X
  109 K, electrons and positions annihilated to
  form low energy gamma-ray photons that can not
  reverse the process
• As a result, matter and anti-matter content
  decreased, and radiation content increased
• From 1 second to 380,000 years, the universe is
  dominated by the radiation (so called primordial
  fireball) derived from the annihilation of
  particles and antiparticles created early by the
  inflation

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Create Ordinary Matter

• If there had been perfect symmetry between
  particles and antiparticles, every particles
  would have been annihilated, leaving no matter at
  all in the universe
• There are 109 photons in the microwave background
  for each proton/neutron in the universe
• Therefore, there is a slight but important
  asymmetry between matter and antimatter
• Right after the inflation, for every 109
  antiprotons, there must have been 109 plus one
  ordinary protons, leaving one surviving after
  annihilation

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Relics of primordial fireball

• When the universe was 3 minutes older, the
  temperature was low enough to pass the deuterium
  (2H, one proton one neutron) bottleneck to
  further produce helium
• At 15 minutes, the temperature of the universe is
  too low for any further nucleosynthesis
• Therefore, the relics of primordial fireball are
  hydrogen, helium (1 helium out of every 10
  protons), and photons (1 billion photons for
  every proton)
• Heavier elements are formed later in the stars,
  not in the early universe

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Cosmic Microwave Background

• Recombination at 377,000 years (T 3000 K)
  after the Big Band, hydrogen (and helium) nuclei
  started to capture electrons to form neutral
  hydrogen (and helium) atoms. The photons mean
  free path becomes effectively infinite
• As a result of recombination, the universe has
  become transparent. This cosmic event is also
  called decoupling
• Cosmic Microwave Background (CMB) the photons
  present at the time of decoupling are the same
  photons that we see in CMB. Therefore, CMB is a
  picture of the universe at the end of
  recombination epoch.
• CMB is observed as a spectrum of uniform black
  body thermal emission form all parts of the sky
  T 2.725 K, f 160.2 GHz, and ? 1.873 mm

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The State of the Universe

• Age 13.7 billion years
• Composition 73 dark energy, 23 dark matter, 4
  ordinary matter

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Galaxies

• This map shows 1.6 million galaxies from the
  2MASS (Two-Micron All-Sky Survey) survey
• Supercluster of Galaxies lie along filaments

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Galaxies
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Our Galaxies
We are located in the middle of the Milky Way
Galaxy 28,000 light years from the center One
of 200 billion stars in our Galaxy
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Star Formation Nebula

• Interstellar gas and dust pervade the Galaxy
• Nebula a cloud of concentrated interstellar gas
  and dust 104 to 109 particles per cubic
  centimeter

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Star Formation Protostar

• Protostar the clump formed from dense and cold
  nebula under gravitational contraction
• The protostar contracts, because the pressure
  inside is too low to support all the mass.
• As a protostar grows by the gravitational
  accretion of gases, Kelvin-Helmholtz contraction
  causes it to heat and begin glowing
• When its core temperatures become high enough to
  ignite steady hydrogen burning, it becomes a main
  sequence star

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Star Formation Protostar
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Star Formation

• A protostars relatively low temperature and
  high luminosity place it in the upper right
  region on an H-R diagram

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Stars
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The Sun
Solar wind creates a big teardrop-shaped
heliosphere around the solar system, by
interacting with the interstellar wind
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The Earth
The Earth 3rd planet from the Sun 1 AU 150
million km Travel time By light -- 8
minutes By Solar Wind-- 100 hrs
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The Sun-Earth Connection

Credit NASA
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Space Weather the Process
It starts from an eruption from the Sun.
Prediction depends on how it propagates
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Space Weather effects
Aurora Geomagnetic Storm
From Space
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Space Weather effects
Adverse effects
Power failure due to March 1989 storm
Damaged transformer
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Space Weather effects
On Human Space Exploration
On crew and passengers of polar-route airplanes
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Space Weather effects
On Satellite Operation
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Space Weather effects
On Communication and Navigation
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Components of Sun-Earth
The driver of Space Weather
Planet
Coronal mass ejections
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Components of Sun-Earth
Heliosphere solar wind
Planet
Spiral magnetic field radial motion of solar
wind combined with Suns rotation
Sprinkler Analogy
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Components of Sun-Earth
Magnetosphere
Planet
A comet-shaped region around the Earth
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Components of Sun-Earth
Magnetosphere
Planet
Electric Currents in Magneto- sphere
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Components of Sun-Earth
Magnetosphere
Planet
Energetic particles in Van Allen radiation belt
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Components of Sun-Earth
Ionosphere
Planet
Density fluctuation affects radio wave reflection
and transmission
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Recent Missions
Hinode
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Recent Missions
STEREO
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Recent Missions
SDO
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The End