The majority of the universe is made up of a currently mysterious entity that pervades space: dark energy. We don’t know exactly what it is, but we do know that dark energy accelerates the expansion of space. We think this means the Universe will expand forever, even as our view of it shrinks while space expands faster all the time.

Crash Course Astronomy Poster: http://store.dftba.com/products/crashcourse-astronomy-poster

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GEOMETRY OF THE UNIVERSE RESOURCES
Geometry:
http://abyss.uoregon.edu/~js/cosmo/lectures/lec15.html
http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question35.html

Expanding faster than light:
http://curious.astro.cornell.edu/legal-information/104-the-universe/cosmology-and-the-big-bang/expansion-of-the-universe/616-is-the-universe-expanding-faster-than-the-speed-of-light-intermediate

General expansion:
https://en.wikipedia.org/wiki/Metric_expansion_of_space

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Table of Contents
Majority of the Universe is Made of Dark Energy 4:35
Dark Energy Accelerates the Expansion of Space 3:42
We Think The Universe Will Expand Forever 5:20

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PHOTOS/VIDEOS
The Big Bang http://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=10128 [credit: NASA]
Collision Scenario for Milky Way and Andromeda Galaxy Encounter http://www.nasa.gov/images/content/654284main_i1220bw.jpg [credit: NASA; ESA; A. Feild and R. van der Marel, STScI]
Artist's impression of vampire star http://www.spacetelescope.org/videos/astro_bn/ [credit: ESO/M. Kornmesser]
Host Galaxies of Distant Supernovae http://www.nasa.gov/sites/default/files/images/593872main_hs-2006-52-a-print.jpg [credit: NASA, ESA, and A. Riess (STScl)]
Dark Energy Expands the Universe http://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=10135 [credit: NASA]
Expanding Universe http://www.spacetelescope.org/videos/hst15_expanding_universe/ [credit: ESA/Hubble (M. Kornmesser & L. L. Christensen)]
Hubble Ultra Deep Field 2014 http://hubblesite.org/newscenter/archive/releases/2014/27/image/a/ [credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)]