Transcript OUR SUN
OUR SUN Solar telescope FUSION Need very high temperatures H + H → He + energy Energy= heat – Light – EM radiation Compositon of the Sun 90% H & 10% He Plasma- gas stripped of electrons Sun Layers core Where Fusion is taking place 15 million ºC Radiative Zone EM radiation is traveling through this zone 2.5 million ºC CONVECTIVE ZONE Convection currents Hot gases rise to surface, cooler gases sink= turbulance Photosphere Sun’s surface Bubbling plasma Only 6,000 ºC! chromosphere Sun’s atmosphere 20,000 C Source of flares/prominences chromosphere CORONA “Crown” See only during solar eclipses 2 million C Made of ions Journey from the center of the sun SUNSPOTS Cool spots on sun Caused by twisting of magnetic field? Oct. 17, 2012 Main sequence star How long is a sunspot cycle? 11 year sunspot cycle Cycle number Solar prominences (filaments) Follows magnetic force of sunspots Can last for weeks to a year harmless Solar flares Violent eruption Last for minutes Can damage satellites Can reach Earthohoh! http://www.youtube.com/watch?v=R 4fX-iFDoDY Coronal Mass Ejections Produced in corona Large storms Can cause power outages, satellite damage and auroras Solar wind Ions are so hot, gravity can’t hold them onto the sun 400 km/sec (1 million mph) Today: speed: 449.5 km/sec AURORAS (Northern lights) caused when Suns’ ions enter Earth’s atm. Auroras from space Solar activity SpaceWeather.com http://www.youtube.com/watch?v=n mDZhQAIeXM&safety_mode=true&p ersist_safety_mode=1&safe=active