Download Energy From the Sun - Duplin County Schools

Energy From the Sun
• The Sun is a main sequence star – stable
• It contains more than 99% of all the mass in
our solar system
• 92% hydrogen; hydrogen and helium together
make up almost 100% (spectroscopic studies)
• 3 distinct layers: the core, the inner zones, and
the atmosphere; no distinct boundaries
The Core
• Makes up ~10% of total diameter of 1,300,000
km
• Temperature – 15,000,000oC; all gas
• Because of its tremendous mass, the Sun has
a very strong gravitational pull; its core is 10
times more dense than Earth’s iron core
Fusion
• Nuclear fusion is the process through which
small atomic nuclei (hydrogen, 1 proton)
combine to form larger nuclei (helium, 2
protons) and releases a tremendous amount
of energy; mass is converted into energy:
E=mc2 where E is energy, m is mass and c in
speed of light (300,000 km/s)
• Temperature must be more than 10,000,000oC
in order for fusion to begin
The Inner Zone
Radiative zone – closest to core
• Temperature is about 2,500,000oC
• Moves energy from atom to atom in the form
of electromagnetic waves (radiation); does not
require a medium, transferred through space
Convective zone
• Energy moved from core moves by convection
currents
The Atmosphere
Uppermost region of solar gases; 3 distinct layers:
1. photosphere – light sphere, made up of
convective gases, about 6000oC; mostly visible
light; considered surface of Sun
2. chromosphere – color sphere, can be 4000 to
50,000oC
3. corona – crown; ~2,000,000oC; thin, keeps most
particles from escaping into space; solar wind
(charged particle that escape through holes)