Sun

6th Grade Science

Composition

• 99.8% of all the mass of solar system• Chemicals

~ 91% Hydrogen~ 9% Helium

Layers

• Interior– Core• Nuclear Fusion (H → He)• 15 million °C• Extreme Pressure

– Radiation Zone• 100,000 years to pass energy through

– Convection Zone• Hot rises / cool falls

Layers

• Outer– Photosphere• Gives off light

– Chromosphere• Thin middle layer• Redish glow

– Corona• White layer only visible during eclipse• Becomes solar wind

Features• Sunspots– Areas of gas as large as Earth– Cooler than other areas– 11 Year cycles

• Prominences– Eruptions near sunspots

• Solar Flares– Rapid release of gas (millions of °C)

• Solar Wind– Particles from sun that cause electrical problems

Formation

• Nebula begins to condense/spin• Sun turns on• Planetesimal = Asteriod bodies• Inner Planets = By collisions– Gases consumed by sun so rock left

• Outer planets– Remaining gases scooped up