Transcript Our Star the Sun

Our Star the Sun
Our Star….. the Sun
The Layers of the Sun
► Corona
– forms the Sun’s outer
atmosphere and can extend far into space.
It can only be seen during an eclipse.
► Chromosphere
– the region below the
corona deep red in color that can only be
seen during an eclipse.
The Sun’s Corona
The Chromosphere
► Photosphere
– this is the part of the sun
seen from Earth where the gases are thick.
Also considered the Sun’s surface.
The Photosphere
► Convective
zone – A part of the sun about
200,000 km thick where the gases circulate
in convection currents.
► Radiative
zone – A very dense region of
the sun about 300,000 km thick where it
takes light millions of years to pass through.
► Core
- the center of the sun where fusion
takes place. Temperatures reach 15,000,000
C.
Internal Structure of the Sun
Nuclear Fusion
► The
process by which two or more atoms
are joined together or fused to form a
larger more massive element.
► In the case of the Sun…. Hydrogen (H)
atoms are fused together to form helium
(He).
► During this process a lot of energy is
produced and released.
Hydrogen Fusion
► The
Sun shines because it is hot.
► The Sun is hot because in its core,
nuclear fusion is producing energy
► The nuclear fusion that is happening in
the Sun's core is the fusion of
hydrogen into helium.
► From models of stars and the Sun, we
estimate that this fusion process will
keep the Sun shining as it does today
for another 4-5 billion years.
Sunspots