magnetic field forms spots magnetic N and S flip so 11yr is really 22yr sun

Magnetic field forms spots magnetic n and s flip so

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magnetic field, forms spots; magnetic N and S flip so 11yr is really 22yr; sun increases brightness with more sunspots (sunspots cooler but regions around them are hotter)Prominences: magnetic loops can extend up into sun’s corona; gas from chromosphere can be trapped in loops; cooler/denser than surrounding corona; forms prominencesSolar Flares: occur when intense magnetic fields in sunspot regions release their energy explosively; occur because of twisting magnet field beneath surface of sunCoronal mass ejections: huge bubbles of gas ejected from the sun, often associated with flaresSolar Storms: Aurora Borealis (Northern Lights) energetic solar wind particles that enter atmosphere can create auroras; charged particles from solar storms can induce currents in power lines and overload grid; can damage or disable satellites; radio interference; Blackout of 1989 in Quebec, can cause blackoutsDistance: parallax = difference in apparent position of an object viewed along two different lines of sight; closest star 40 tril km away, Alpha Centauri SystemoParallax is used to measure the distance to stars that are relatively nearby; nearby stars appear to sweep through angle shown, half angle is parallax, p.oLarger the parallax angle, the closer the star; HipParCos (high precision parallax collecting satellite), measures positions of 100,000+ stars accuratelyoApparent brightness: brightness of a star as it appears to our eyes (depends on intrinsic brightness and distance)oIntrinsic brightness: measure of total light emitted; greater the distance, light spread out over larger area, less brightnessoIf the distance between two objects doubles, apparent brightness drops by a factor of 4 (inverse-square law)
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Luminosity: solar luminosities: sun = 1 Lsun; to determine: observe apparent brightness, measure distance using parallax; from .0001 Lsun to 1,000,000 LunMass: observe mass by observing stars orbiting each other; Alcor & Mizar (multistar system), Horse and Rider oStars in binary system orbit around each other, find center of mass; massive star travels in smaller orbit, lower mass moves faster in larger orbitoKepler’s 3rdlaw to determine masses of the stars (p^2= a^3); for planets orbiting sun: M1+M2=1Msun; P^2=(a^3/(M1+M2))oMost massive stars: 150Msun, least massive stars: 0.08MsunMass-Luminosity Relationship: more massive stars are more luminousSurface Temperatures: Joseph von Fraunhofer found solar spectrum interrupted by dark lineso3 basic types of spectra: continuous (complete rainbow of colors; hot opaque body (dense gas/solid) produces); emission lines (bright lines against dark background; hot transparent gas produces); absorption lines (dark lines among colors of continuous spectrum; transparent gas in front of continuous spectrum produces)oAtoms absorb specific colors (wavelengths) of light and later re-emit the energy, forming spectrum lines; each atom produces unique set of lines, compositiono
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