The SunThe Sun

Our SunOur Sun

Classification: GClassification: G

Temperature: 6000 KTemperature: 6000 K

Age: 6 Billion Years Age: 6 Billion Years Old Old

CompositionComposition 73.4% Hydrogen73.4% Hydrogen 25% Helium25% Helium

The SunThe Sun

Sun’s LayersSun’s Layers The Solar InteriorThe Solar Interior Visible SurfaceVisible Surface PhotopsherePhotopshere Atmospheric Atmospheric

ChromosphereChromosphere

CoronaCorona

Sun’s AtmosphereSun’s Atmosphere

Sun’s Surface FeaturesSun’s Surface Features

The Fusion Process of the Sun Provides the The Fusion Process of the Sun Provides the Sun with Violent Surface FeaturesSun with Violent Surface Features

SunspotsSunspots

Magnetic FieldsMagnetic Fields

Coronal Mass EjectionsCoronal Mass Ejections

SunSun

PhotospherePhotosphere

PhotospherePhotosphere Photos = LightPhotos = Light Sphere = BallSphere = Ball 500 km Thick500 km Thick Grainy Texture (Size of Texas)Grainy Texture (Size of Texas) Composition is revealed by the dark lines in Composition is revealed by the dark lines in

absorption spectrumabsorption spectrum

Solar GranulesSolar Granules

What Causes the Granule Look?What Causes the Granule Look?Convection CurrentsConvection Currents

SunspotsSunspots

SunspotsSunspots

Darker Areas Darker Areas Surrounding Hotter AreasSurrounding Hotter Areas

Temporary FeaturesTemporary Features May Last Days, Weeks, or May Last Days, Weeks, or

MonthsMonths

Cyclic Cyclic 10-11 year Patten10-11 year Patten Increase and Decrease in Increase and Decrease in

FrequencyFrequency Solar Activity CylceSolar Activity Cylce

How Do Sunspots DevelopHow Do Sunspots Develop

Magnetic FieldMagnetic Field

Sunspots are Related to Magnetic FieldSunspots are Related to Magnetic FieldMagnetic Fields cause prominencesMagnetic Fields cause prominences Huge arching gas columnsHuge arching gas columns

Violent eruptions near a sunspot are called solar Violent eruptions near a sunspot are called solar flaresflares

Sun’s AtmosphereSun’s Atmosphere

The Sun’s Atmosphere has Two LayersThe Sun’s Atmosphere has Two Layers

ChromosphereChromosphere 2000 km above Photosphere2000 km above Photosphere

CoronaCorona Extends millions of miles into space Extends millions of miles into space Temp as high as 2 Million Degrees KelvinTemp as high as 2 Million Degrees Kelvin Particles are released as Solar WindParticles are released as Solar Wind

ChromosphereChromosphere

ChromosphereChromosphere A relatively thin layer of hot gases a thousand A relatively thin layer of hot gases a thousand

km thickkm thick Can be seen during a solar eclipseCan be seen during a solar eclipse Produces an emission spectrumProduces an emission spectrum

CoronaCorona

CoronaCorona Outermost portion of the solar atmosphereOutermost portion of the solar atmosphere Can be seen during a solar eclipseCan be seen during a solar eclipse Extends a few a thousand km into spaceExtends a few a thousand km into space Creates the solar windCreates the solar wind 1 million degrees K1 million degrees K

Solar FlaresSolar Flares

Solar FlaresSolar Flares Are brief outburst that normally last about an Are brief outburst that normally last about an

hourhour appear as a sudden brightening of the region appear as a sudden brightening of the region

above a sunspot clusterabove a sunspot cluster Produces AurorasProduces Auroras

Solar ProminencesSolar Prominences

Solar FlareSolar Flare

Coronal Mass EjectionCoronal Mass Ejection

Bright, appear as a halo around the Sun Bright, appear as a halo around the Sun when emitted in the Earth’s Directionwhen emitted in the Earth’s Direction

Highly Charged Solar Wind Particles can Highly Charged Solar Wind Particles can disrupt radio signals (cell phones)disrupt radio signals (cell phones)

Near Earth Polar Areas Solar wind can Near Earth Polar Areas Solar wind can create lightcreate light Northern LightsNorthern Lights

Northern LightsNorthern Lights

Causes of the Northern LightsCauses of the Northern Lights

Northern LightsNorthern Lights

Color of the AuroraColor of the Aurora

Fun Facts of the AuroraFun Facts of the Aurora

Brilliant auroras often occur at 27-day intervals as active Brilliant auroras often occur at 27-day intervals as active areas on the sun's surface face earth during its 27-day areas on the sun's surface face earth during its 27-day rotation cycle. rotation cycle. Northern lights are more frequent in late autumn and Northern lights are more frequent in late autumn and early spring. October, February and March are the best early spring. October, February and March are the best months for auroral observations in northern Norway. months for auroral observations in northern Norway. Northern lights activity corresponds closely to sunspot Northern lights activity corresponds closely to sunspot activity, which follows an 11-year cycle, but there seems activity, which follows an 11-year cycle, but there seems to be a one-year delay between sunspot maximum and to be a one-year delay between sunspot maximum and maximum auroral occurrence. maximum auroral occurrence. Northern lights activity is 20-30% less during solar Northern lights activity is 20-30% less during solar minimum than at solar maximum. minimum than at solar maximum.

Fun Facts ContinuedFun Facts Continued

Andenes, NorwayAndenes, NorwayAlmost every dark and clear nightAlmost every dark and clear nightFairbanks, AlaskaFairbanks, AlaskaFive to ten times a monthFive to ten times a monthOslo, NorwayOslo, NorwayRoughly three nights a monthRoughly three nights a monthNorthern Scotland, Great BritainNorthern Scotland, Great BritainRoughly once a monthRoughly once a monthUS/Canadian borderUS/Canadian borderTwo to four times a yearTwo to four times a yearMexico and Mediterranean countriesMexico and Mediterranean countriesOnce or twice a decadeOnce or twice a decadeSouth of the Mediterranean countriesSouth of the Mediterranean countriesOnce or twice a centuryOnce or twice a centuryEquatorEquatorOnce in two hundred yearsOnce in two hundred years

Sun’s InteriorSun’s Interior

The Ultimate Power PlantThe Ultimate Power Plant

Nuclear FusionNuclear Fusion Coverts four H atoms into the nucleus of a Coverts four H atoms into the nucleus of a

Helium atomHelium atom Internal temp. needs to be several million Internal temp. needs to be several million

degreesdegrees Where does the temp come from?Where does the temp come from?

Compression of the gases that form the sunCompression of the gases that form the sun

Increase Pressure = Increase TemperatureIncrease Pressure = Increase Temperature

Production of EnergyProduction of Energy

Nuclear FusionNuclear Fusion

Joining of AtomsJoining of Atoms

Proton – Proton Proton – Proton ChainChain Starts with two Starts with two

Protons and Ends with Protons and Ends with Helium Helium

ENERGYENERGY