The Sun – El Sol – Die Sonne ESPS- Palmer High School

Interesting Facts about the sun  SC3#view=detail&mid=F72C15A1770A0A936D5FF72C1 5A1770A0A936D5F SC3#view=detail&mid=F72C15A1770A0A936D5FF72C1 5A1770A0A936D5F

How big is the sun?  About 110 times wider than Earth  1.3 million times bigger than Earth  Sun is 865 thousand miles wide

Composition of the sun (what is it made of?)  Contains 99.8% of the entire mass of Solar System  Earth’s primary source of energy  Made of Gases (what 2 types of gases?)  Hydrogen 70%  Helium 28%

How does the sun produce energy?  The Sun produces energy by the nuclear fusion of hydrogen into helium in its core. yS2WmT9NM

Inside of the sun  Core  Radiative Zone  Convection zone

Nuclear Fusion  hydrogen atoms in the core are crushed together (fused) into a helium atom  This energy is then radiated out from the core and moves across the solar system.  This is radiation (gamma rays)

Hydrogen yields Helium + ENERGY Great Pressure

The Sun’s Atmosphere  Photosphere- surface from which the solar light that we see is emitted -- temperature 6000°C  Chromosphere- layer above the photosphere hydrogen at this temperature gives the sun its color – temperature 20,000°C  Corona- outer atmosphere of the Sun -- temperature of millions of degrees (but it is 10 billion times less dense than the atmosphere of the Earth at sea level)

Features of the sun  Sun Spots- These are dark, cool areas that appear on the photosphere. Sunspots always appear in pairs and are intense magnetic fields (about 5,000 times greater than the Earth's magnetic field) that break through the surface. Caused by movement of gases.

Features of the sun continued…  Solar Flares sudden, violent explosions from the sun.  release gas, electrons, visible light, ultraviolet light and X-rays  caused by sudden magnetic field changes in areas where the sun's magnetic field is concentrated.

Effects of Solar Flares  When charged particles reach the Earth's magnetic field, they interact with it at the poles to produce the auroras  Solar flares can disrupt communications, satellites, navigation systems and even power grids

Sun features continued….CME’s coronal mass ejections  Solar flares twist back on themselves and cut off from the sun  Release packet of plasma into space  Plasma is superheated electrically charged gas

Coronal Mass Ejection (CME’s) This series of images of coronal mass ejections taken with LASCO C3 (May 1-31, 1997) at ay97sm.mpg ay97sm.mpg Effects of CME Can damage satellites and communications Very dangerous to astronauts Power problems

Features of the sun continued… Solar Wind  Blows charged particles and magnetic fields away from the Sun  Charged particles captured by Earth’s magnetic field  Create Auroras or Northern and Southern Lights Auroras Electrons from solar wind are captured by the Earth’s magnetic field Interact with atoms in our atmosphere: oxygen and nitrogen make red and green; nitrogen can also make violet Northern lights are Aurora Borealis, while southern are Aurora Australis wind.mpg

How does the sun affect the Earth?  Gravity - Orbits- The Sun’s powerful gravity keeps the planets in orbit  Radiation - Our Sun (and all active stars) emits radiation Radio, infrared, visible, ultraviolet, x-ray and even some gamma rays. Most of the sunlight is yellow-green visible light  The Earth’s atmosphere filters out some frequencies Ozone layer protects us from some ultra-violet, and most x-rays and gamma rays  Sunlight is absorbed by Earth The Sun does NOT send “heat rays” into space. Some of its light is infrared, but that is not the same thing as heat. The Sun’s light is absorbed by Earth (clouds, plants, oceans, rock…) By absorbing the light, we are transforming it into heat energy

How does our Sun compare to other Stars?  Active stars range in size from supergiants to dwarfs- Our sun is a dwarf with medium mass  Stars range from very bright (supergiants) to very dim (dwarfs)-Our Sun is a medium-bright dwarf  Stars range from very hot blue on the outside (O class) to cool red on the outside (M class)-Our Sun is in- between--yellow

So is our Sun an average star?  No—most stars are smaller and cooler than our Sun BUT  Most of the bright stars we see are bigger and hotter amazing-time-lapse-videos-stars-landscapes-and-urban- scenes/page/3/#slide-top