lecture 22, november 18, 2010
DESCRIPTION
LECTURE 22, NOVEMBER 18, 2010. ASTR 101, SECTION 3 INSTRUCTOR, JACK BRANDT [email protected]. Question 2. a) ongoing star formation b) a disk, bulge, and halo c) globular clusters in the halo d) open clusters in the disk e) all of the above. What property is shared by spiral galaxies?. - PowerPoint PPT PresentationTRANSCRIPT
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LECTURE 22, NOVEMBER 18, 2010
ASTR 101, SECTION 3INSTRUCTOR, JACK BRANDT
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a) ongoing star formationb) a disk, bulge, and haloc) globular clusters in the halod) open clusters in the diske) all of the above
Question 2
What property is shared by spiral galaxies?
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a) ongoing star formationb) a disk, bulge, and haloc) globular clusters in the halod) open clusters in the diske) all of the above
Question 2
What property is shared by spiral galaxies?
M-51, a Type Sb spiral
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a) giant globular clusters in the halo.b) small irregular galaxies that orbit the Milky
Way.c) large molecular clouds in the disk of our
Galaxy.d) the brightest ionized hydrogen regions in
our Galaxy.e) spiral nebulae originally discovered by
Herschel.
Question 3
The Magellanic Clouds are
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a) giant globular clusters in the halo.b) small irregular galaxies that orbit the Milky
Way.c) large molecular clouds in the disk of our
Galaxy.d) the brightest ionized hydrogen regions in
our Galaxy.e) spiral nebulae originally discovered by
Herschel.
Question 3
The Magellanic Clouds are
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a) more distant galaxies showing greater blueshifts.
b) distant quasars appearing proportionally dimmer.
c) more distant galaxies showing greater redshifts.d) slowly varying Cepheid variables appearing
brighter.e) more distant galaxies appearing younger.
Question 5
Hubble’s law is based on
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a) more distant galaxies showing greater blueshifts.
b) distant quasars appearing proportionally dimmer.
c) more distant galaxies showing greater redshifts.d) slowly varying Cepheid variables appearing
brighter.e) more distant galaxies appearing younger.
Question 5
Hubble’s law is based on
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Question 6
Hubble’s constant measures
a) the density of galaxies in the universe.b) the luminosity of distant galaxies.c) the reddening of light from dust clouds.d) the speed of a galaxy.e) the rate of expansion of the universe.
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a) the density of galaxies in the universe.b) the luminosity of distant galaxies.c) the reddening of light from dust clouds.d) the speed of a galaxy.e) the rate of expansion of the universe.
Question 6
Hubble’s constant measures
Hubble’s law relates how fast galaxies are moving away from us at different
distances.
A larger value for H0 implies a faster expansion rate.
Velocity = H0 x Distance
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a) the size of the universe.b) distances to galaxies.c) the speed of recession of galaxies.d) the density of matter in the universe.e) the temperature of the Big Bang.
Question 7
To calibrate Hubble’s constant, astronomers must determine
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a) the size of the universe.b) distances to galaxies.c) the speed of recession of galaxies.d) the density of matter in the universe.e) the temperature of the Big Bang.
Question 7
To calibrate Hubble’s constant, astronomers must determine
Distances to galaxies are determined using a variety of “standard candles,” including
Cepheid variables, supernova explosions, model galaxies, and model clusters.
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a) supermassive black holes at their cores.b) dark matter.c) self-sustaining star formation.d) spiral density waves.e) hypernova explosions.
Question 10
Seyfert and radio galaxies could be powered by
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a) supermassive black holes at their cores.b) dark matter.c) self-sustaining star formation.d) spiral density waves.e) hypernova explosions.
Question 10
Seyfert and radio galaxies could be powered by
The Circinus Galaxy, a Seyfert galaxy
about 4 Mpc away
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