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Patricia BurchatDepartment of Physics
Stanford University
Dark Matter, Dark Energy: Mysteries of the Universe
Hubble Space TelescopeUltra Deep Field
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Patricia BurchatDepartment of Physics
Stanford University
Dark Matter, Dark Energy: Mysteries of the Universe
Dark Energy70%
Dark Matter26%
Ordinary Matter4%
Hubble Space TelescopeUltra Deep Field
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http://janus.astro.umd.edu/javadir/orbits/ssv.html
Planetary Motion
Credit: The Astronomy WorkshopA collection of interactive web-based programs for introductory astronomy as well as more advanced courses.
Written by Doug Hamilton and Mike Asbury, http://www.astro.umd.edu/education/education.html
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The Andromeda Galaxy4
Doppler Shift
Windows to the Universe: http://www.windows.ucar.edu
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Doppler Shift
JPL Planet Quest: http://planetquest.jpl.nasa.gov/science/finding_planets.cfm
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The Andromeda Galaxy7
The Coma Cluster of Galaxies(visible light)
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The Coma Cluster of Galaxies(x ray, ROSAT image)
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Gravitational Lensing
http://www.goshen.edu/nasc/NaSc200/Notes/Galaxies/GravLensDiagram.JPG
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Gravitational Lensing by Galaxy Cluster Abell 2218
Hubble Space Telescope, WFPC2 and ACS
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The Bullet Cluster
PINK = gas; BLUE = dark matter
Clowe et al., astro-ph/0608407
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Simulation from Center for Cosmological Physics, University of Chicago
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Dark Energy70%
Dark Matter26%
Ordinary Matter4%
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Expanding Universe
© 1998 Edward L. Wright.
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Redshift due to the Expansion of Space
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Standard Candles in the Universe:Type Ia Supernovae
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Evolution of a Supernova
Supernova Cosmology Project (P. Nugent: spectral sequence; A. Conley: image sequence) with the help of Lawrence Berkeley National Laboratory's Computer Visualization Laboratory
(N. Johnston: animation) at the National Energy Research Scientific Computing Center.
Time
Wavelength
Brightness
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Calan/Tololo (Hamuy et al, A.J. 1996)
Supernova Cosmology Project
effe
ctiv
e m
B
(0.5,0.5) (0, 0)
( 1, 0 ) (1, 0)(1.5,–0.5) (2, 0)
!!""!##$%$$
( 0, 1 )
Fla
t
#$%$&
redshift z
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0.02 0.05 0.1 0.2 0.5 1.00.02 0.05 0.1 0.2 0.5 1.0
Perlmutter, et al. (1998)
FA
INT
ER
(Far
ther
)(F
urt
her
bac
k in
tim
e)
MORE REDSHIFT(More total expansion of universe since the supernova explosion)
In flat universe: !M = 0.28 [' 0.085 statistical] [' 0.05 systematic]
Prob. of fit to # = 0 universe: $()
• For a given brightness (distance), redshift is less than expected.• Universe was expanding at less than the “expected” rate in the past.• Universe is actually expanding at an ever-increasing rate today!
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Future Investigations of Dark Matter
andDark Energy:
An Example
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Large Synoptic Survey Telescope
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Large Synoptic Survey Telescope
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Dark Energy70%
Dark Matter26%
Ordinary Matter4%
Dark Matter, Dark Energy: Mysteries of the Universe
Hubble Space TelescopeUltra Deep Field
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