LECTURE 22, NOVEMBER 18, 2010

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LECTURE 22, NOVEMBER 18, 2010

ASTR 101, SECTION 3INSTRUCTOR, JACK BRANDT

jcbrandt@unm.edu

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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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