The Sun – El Sol – Die SonneESPS- Palmer High School

Interesting Facts about the sun

http://www.bing.com/videos/search?q=Sun&FORM=HDRSC3#view=detail&mid=F72C15A1770A0A936D5FF72C15A1770A0A936D5F

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.

http://www.youtube.com/watch?v=4iyS2WmT9NM

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

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

The Sun’s Atmosphere

Photosphere- the photosphere may be thought of as the imaginary surface from which the solar light that we see appears to be emitted.

Chromosphere- The chromosphere is an irregular layer above the photosphere where the temperature rises from 6000°C to about 20,000°C. At these higher temperatures hydrogen emits light that gives off a reddish color

Corona- This extended outer atmosphere of the Sun has a 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 continued…

Solar Flares occur at times in complex sunspot groups, they are abrupt, violent explosions from the sun. Solar flares are thought to be caused by sudden magnetic field changes in areas where the sun's magnetic field is concentrated. They're accompanied by the release of gas, electrons, visible light, ultraviolet light and X-rays. When this radiation and these particles reach the Earth's magnetic field, they interact with it at the poles to produce the auroras (borealis and australis). Solar flares can also disrupt communications, satellites, navigation systems and even power grids

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.

Sun features continued….CME’s coronal mass ejections. Clouds of gases from the chromosphere will rise and

orient themselves along the magnetic lines from sunspot pairs and form arches called prominences.

Prominences can erupt for hours and send large amounts of charged material racing through the corona and outward into space at 600 miles per second (1,000 kilometers per second)

These eruptions of material are called Coronal Mass Ejections

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

http://www.treehugger.com/slideshows/natural-sciences/12-most-amazing-time-lapse-videos-stars-landscapes-and-urban-scenes/page/3/#slide-top

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

http://sohowww.nascom.nasa.gov/bestofsoho/Movies/animation/Solarwind.mpg

Coronal Mass Ejection (CME’s) CME is a massive burst of solar wind and magnetic fields

rising above the solar corona or being released into space

This series of images of coronal mass ejections taken with LASCO C3 (May 1-31, 1997) at http://sohowww.nascom.nasa.gov/bestofsoho/Movies/C3May97/C3May97sm.mpg

Effects of CME• Can damage satellites• Very dangerous to astronauts• Power problems

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 or close to it

The Earth’s atmosphere filters out some frequencies Ozone layer protects us from some ultra-violet, and most x-rays and gamma rays Water and oxygen absorb some radio waves Water vapor, carbon dioxide, and ozone absorbs some infrared

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