Exam 13: Galaxies: Normal and Active

According to the unified model of active galactic nuclei, a ____ is observed if our line of sight is parallel to the plane of the dense disk of an active galactic nucleus (the direct view of the nucleus is blocked by dust in the disk).

In the double-exhaust model, the radio lobes of a radio galaxy are inflated by

If the redshift of a quasar were 3, at what wavelength would the 486.1-nm line of hydrogen appear in the quasar's spectrum?

Poor clusters

The unified model describes active galactic nuclei using

Gravitational lensing

Seyfert galaxies are spiral galaxies with active cores.

____________________ galaxies have a definite disk component, but contain no evidence of spiral pattern, few hot young stars, and little gas and dust.

Which one of the words below is a name for a type of galaxy in the Hubble classification system?

The high ____________________ of quasars reveals to astronomers that they must be very distant.

The central galaxy in a double-lobed radio source is usually

How does the study of quasars reveal information of the history of the universe?

The spectrum of a(n) ____________________ consists of a continuous spectrum and a few highly redshifted emission lines of due to hydrogen.

A spiral (S or SB) galaxy contains

Active galaxy radio lobes and jets contain magnetic fields.

The rotation curve of a galaxy can be used to determine

In the unified model of active galactic nuclei, the broad line region in an active galactic nucleus is

What evidence do we have that active galaxies are powered by black holes at their centers?

Elliptical galaxies contain more gas, dust, and young stars than do Sa galaxies.

If Hubble's constant is taken to be 70 km/s/Mpc, and a quasar is found with a radial velocity of 0.95 times the speed of light, how far away is the quasar?