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Astronomy:. Here is my powerpoint from last years coaches conference. I will be updating it to reflect the changes in content in this years rules. I’m not sure yet how to test 50 teams at States on the use of DS9 image viewing software, and won’t use it at all for regionals.
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Here is my powerpoint from last years coaches conference. I will be updating it to reflect the changes in content in this years rules. I’m not sure yet how to test 50 teams at States on the use of DS9 image viewing software, and won’t use it at all for regionals.
Parallax • Stellar parallax: angle abc • Parallax angle: ½ angle abc • Parsec: distance to a star with 1” parallax angle • Parsec: ~31 trillion km (19 trillion miles) • Parsec: 3.26 light years
Parallax • Star's distance (pc) = 1 / parllax (“) • Useful for stars up to about 100pc
Magnitude • Apparent magnitude (m) • Hipparchus 1 to 6 • Lower numbers brighter • Absolute magnitude (M) • Corrected to standard distance of 10pc • Can be determined form spectra • Distance modulus: m – M
Hubble Constant • v = Hd • Ho = ~ 74 km/sec/Mpc (~ 23 km/sec/MLY)
Age of universe • v = Hd • H = v/d • 1/H = d/v = time • 1/Ho = age of the universe
Schwarzschild radius (Rs) • Radius to become a black hole • Rs = 2GM/c2 • G = gravitational constant • M = mass of the body • C = speed of light • Object > 3 solar masses become black holes
Wien & Stefan-Boltzman • λmax = 0.3/T • T = temperature in Kelvin • Total energy emitted is proportional to the fourth power of the absolute temperature • A star 2x sun's temperature emits 16x more energy • 24 = 16
Open Clusters • 100 to 10,000 loosely packed • Concentrated in spiral arms • Young • Hot • Highly luminous • Like certain vampires
Globular Clusters • In halo around galactic disk • 100,000 to 1 million tightly packed stars • Old stars (like Lon Chaney Jr)
Population I Stars • Hottest & brightest • young • In disc, spiral arms • Relatively high in heavier elements • In dust and gas formed from
Population II Stars • Galactic nucleus and halo • Older • Almost entirely H & He
Galaxy Classifications • Elliptical • practically all old stars • Some gas and dust • Normal Spiral and Barred Spiral • Various ages • Lots of gas and dust in the disk • Irregular • Mostly young bright stars, ionized gas
More Galaxies • Lenticular • Bright, flat disc • No arms • No recent stars • Dwarf • Low mass and luminosity • Active Galaxies • AGN emits lots of energy • Black hole?
Distances • Cephid variables • Standard galaxies • Tully-Fisher Relation? • 21cm spectral line width • Luminosity of spiral galaxies
Galaxy Clusters • Regular • Compact, high density center • Mostly elliptical and lenticular • Many with active galaxy emition • Irregular • Our local group • Looser structure, little central density • Spirals and irregulars • Super clusters • On edges of voids
Featured Objects • Where are they • What are they • Special characteristics? • Images?