Our Sun

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Our Sun
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The Sun

• Largest object in the solar system
• The sun has 99 of all mass in the solar system
• It is low densitysimilar to gas giants
• The sun controls motions of all objects in the
  solar system
• Planets
• Comets
• Asteroids

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Layers of the Sun
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Layers of the sun

• Core is the innermost layer
• It is more dense than lead, but not solid
• It is the site of nuclear fusion
• 18,000,000 oF!
• Photosphere is lowest layer of Suns atmosphere
• 400 km thick
• It is the visible layer of the sun
• Thought of as the surface of the sun
• 10,000 oF

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• Chromosphere is the middle layer of Suns
  atmosphere
• 55,000 oF
• Visible only with filters as a red aura
• Corona is the top most layer of Suns atmosphere
• Visible only during a solar eclipse
• 1.7 t0 3.5 million oF
• Extends several million km above chromosphere

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Other features of the Sun

• Solar wind is gas flowing outward from Sun at
  high speeds
• 400 km/s
• Charged particles from the wind are trapped in
  Van Allen belts and can be seen as aurora
  borealis northern lights
• Solar flares are eruptions of radiation
• Prominence are large jets of gas (loops)

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Northern Lights as seen from Earth
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How Northern Lights Work
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Sunspots

• Sunspots are dark spots on Suns surface
• Suns magnetic field breaks through photosphere
• Appear darker because of cooler temp.

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Close up of sunspot
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Solar Prominences
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The Suns Energy

• Nuclear fusion of Hydrogen into Helium
• Not all of Suns energy reaches Earth because of
  the atmosphere
• Our sun is middle aged having converted half of
  its Hydrodgen

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Visible light

• Spectrum is the arrangement of visible light
  based on wavelength
• Violet is the shortest wavelength
• Red is the longest wavelength
• 3 types of light
• Absorption
• Emission
• Continuous