Chapter 26
The Sun
The Sun
•Is a star
•Is a main sequence star
•1 million Earth’s would fit inside
the sun
•1.4 million kilometers from earth
• Hertzberg- Russel
Diagram
• Shows stars in their
different stages
• Fuel for the Sun is
Fusion..
• The union of hydrogen
atoms into helium
• 4H = 1 He
• What happens when a
star runs out of its fuel
– hydrogen?
• It either becomes a red
giant or a supergiant
• Our sun will become a
red giant
Star life cycle
•Sun’s layers
•Core
•Photosphere
•Chromosphere
15,600,000 oC – dense!
The apparent bright yellow surface of
Outer layer around the photosphere – r
Corona
•Thin outer atmosphere….only part
•Solar Prominences
•Solar Prominences
• Solar Flare
• Strong magnetic storm
on the surface of the
sun – thousands of
miles tall!
• Sunspots
• Dark spots on the
photosphere
• Areas of high
magnetic field 1000X stronger
• They appear to move
so they gave proof that
the sun rotates
•Solar Prominences
•Flow of electrically charged pa
•Cause auroras
What is the center of our solar
system?
• Geocentric
• Ptolemy’s theory of an
Earth-centered solar
system
• Geo – mean EARTH
• -centric means
CENTERED
• Early astronomers thought
that everything revolved
around the earth –
WRONG!!!!!!
• Heliocentric
• Copernicus’ idea of a
sun-centered solar
system