In order to understand how we study the universe, we need to talk a little bit about light. Light is a form of energy. Its wavelength tells us its energy and color. Spectroscopy allows us to analyze those colors and determine an object’s temperature, density, spin, motion, and chemical composition.

Check out the Crash Course Astronomy solar system poster here: http://store.dftba.com/product....s/crashcourse-astron

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Chapters:
Introduction 00:00
Light is a Wave 0:31
Electromagnetic Spectrum 1:32
How is Light Made? 3:19
Atomic Structure 4:47
Spectroscopy 7:14
Redshift vs Blueshift 8:26
Review 9:50

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PHOTOS/VIDEOS
Wavelengths http://imagine.gsfc.nasa.gov/e....ducators/gammaraybur [credit: Imagine the Universe! / NASA]
Observatories across spectrum http://imagine.gsfc.nasa.gov/I....mages/science/observ [credit: Imagine the Universe! / NASA]
Red hot spiral hotplate http://freefoodphotos.com/imag....elibrary/cooking/sli [credit: freefoodphotos.com]
The Crab Nebula http://en.wikipedia.org/wiki/N....ebula#/media/File:Cr [credit: NASA, ESA, J. Hester and A. Loll (Arizona State University)]
Building the Space Telescope Imaging Spectograph http://imgsrc.hubblesite.org/h....u/gallery/db/spacecr [credit: NASA]
VST images the Lagoon Nebula http://en.wikipedia.org/wiki/L....agoon_Nebula#/media/ [credit: ESO/VPHAS+ team]
Jupiter http://www.nasa.gov/images/con....tent/414987main_pia0 [credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute]
Venus http://en.wikipedia.org/wiki/A....tmosphere_of_Venus#/ [credit: NASA - NSSDC Photo Gallery Venus]
Ring Around SN 1987a, image 1 http://www.spacetelescope.org/images/opo9714e/ [credit: Jason Pun (NOAO) and SINS Collaboration]
Ring Around SN 1987a, image 2 http://www.spacetelescope.org/images/opo9714a/ [credit: George Sonneborn (GSFC) and NASA/ESA]