The Solar System The Sun Objectives Describe the

The Solar System The Sun

Objectives -Describe the basic structure and composition of the sun -Explain how the sun generates energy -Describe the surface activity of the sun, and identify how this activity affects Earth

Did You Know? ? ? 1) 99% of the solar systems mass is concentrated in the sun. 2) The temperature of the center of the sun is 26, 999, 540 o. F 3) The surface temperature of the sun is about 11, 000 o. F – Source - http: //www. factscollection. com/Cosmic%20 Space-2. html

The Sun

The Structure of the Sun

Parts of the Sun • Corona – The outer layer of the sun’s stmosphere • Chromosphere – Thin area below the corona • Photosphere – The visible part of the sun we see from earth • Convection Zone – Area where gasses circulate • Radioactive Zone – Dense region below the Convection Zone • Core – Center of the sun where energy is produced

The Structure of the Sun

Parts of the Sun

Is the Sun burning? ? ? • For many years scientists thought the sun burned fuel to generate energy • The Sun does NOT burn – If the sun was burning it would only last for 10, 000 years before it ran out of fuel

Nuclear Fusion • Nuclear Fusion – The process where 2 or more nuclei join together (fuse) – During this process, a massive amount of energy is created • Albert Einstein proved this with his famous formula E = mc 2 – Energy = mass. speed of light 2

Nuclear Fusion • Because of the high temperatures and pressure of the sun, Nuclei of Hydrogen, which would normally repel each other are smashed creating helium. – This creates a massive amount of energy

Nuclear Fusion of the Sun

Solar Activity • Sunspots – A dark area of the photosphere of the sun that is cooler than the surrounding areas – It also has a strong magnetic field • Sunspots last about 11 years

Sunspots

Solar Activity • Solar Flares – Regions of extremely high temperatures – Solar flares can extend several thousand kilometers within minutes – Solar flares usually occur near sunspots • They can interrupt radio communication on Earth

Solar Flares

Earth’s Magnetic Field

Solar Flares and Earth

Review • The photosphere is the visible part of the sun on the earth • The Sun is not burning, it creates energy through nuclear fusion • The sun’s nuclear fusion comes from changing hydrogen into helium • Sunspots are colder spots on the suns surface • Solar Flares are hit spots that shoot out from the sun • Earths magnetic field and atmosphere protect it from the sun