Here Comes the Sun!!

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Here Comes the Sun!!
Chapter 14 Section 2 Page 545

• Miss Sullivan
• Rm B2

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The Sun

• The sun is the closest star to Earth
• It is approximately 93 million miles or 150
  million kilometers away (1 astronomical unit)
• It provides almost all of the energy for life on
  Earth
• It also accounts for 99.8 of the total mass of
  our solar system

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The Suns Energy

• The suns energy is produced through nuclear
  fusion.
• Nuclear fusion is when two smaller atomic nuclei
  (hydrogen) are fused or joined together to form a
  more massive nucleus (helium) and releasing
  energy.
• This fusion happens only under intense pressure
  and temperature

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Nuclear Fusion

• During nuclear fusion, two atomic nuclei collide
  and fuse.

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Forces in Balance

• Nuclear fusion in the suns core produces an
  incredible amount of energy.
• This energy causes gas ions within the sun to
  move very fast, generating a tremendous pressure
  pushing outward from the core.
• This pressure would cause the sun to explode if
  it werent balanced by an equal and opposite
  force The balancing force is gravity.
• The weight of matter pushing inward and the
  outward pushing pressure are balanced throughout
  the sun.

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The Layers of the Sun

• The sun has an interior and an atmosphere, each
  of which consists of several layers.

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The Suns Interior

• Convection Zone --- where hot gases form
  convection currents
• Radiation Zone --- a place of condensed gases
  that transfer electromagnetic radiation
• The Core --- where nuclear fusion takes place

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The Suns Atmosphere

• The suns atmosphere has 3 layers
• The Photosphere
• the sphere that gives off light
• The Chromosphere
• a thin layer of color
• The Corona
• the outer white halo that extends millions of
  kilometers into space

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The Sun

• Features on or above the sun include sunspots,
  prominences, and solar flares.

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Sunspots

• Sunspots look like small dark areas on the suns
  surface (some are actually as big as the Earth!)
• Sunspots are areas of gas on the sun that are
  cooler than the gases around them.
• Cooler gases dont give off as much light as the
  hotter gases.
• Sunspots actually occur in cycles and can be
  linked with weather here on Earth!

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Sunspots and Weather

• Evidence that supports that theory that sunspots
  cycles influence weather include
• Little Ice Age most parts of the world
  experienced cold harsh weather.
• Little Ice Age is associated with low sunspot
  activity between 1645-1715 (these are called
  minimums)
• Low sunspot activity occurs every 500 years,
  perhaps another Little Ice Age will occur in
  2050! (41 years from nowhow old will you be?)

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Prominences

• Prominences Reddish loops of ionized gas that
  link different parts of sunspot regions.

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Solar Flares

• Solar Flares When prominences suddenly connect,
  a large amount of energy is released causing huge
  explosions of hydrogen (Solar Flares)

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Solar Wind

• Solar flares cause an increase in solar wind that
  extends the corona into space
• An increase is solar winds can cause
  electromagnetic effects on Earth auroras,
  disrupt communications, cause electrical problems

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Homework

• Read Chapter 14, Section 2
• Do the questions at the end of the section, page
  550