Some quasars show absorption spectra with a smaller redshift than their emission spectra. This indicates that
A) they are much closer than previously thought.
B) there is cooler gas between us and the quasar.
C) we still don't understand redshifts.
D) their black holes are still contracting.
E) their black holes are still expanding.
Question 2
Redshift surveys give us
A) a 3-D layout of galaxies in space.
B) a better value of the speed of light.
C) an idea of how turbulent the intergalactic gas is.
D) the total mass of the universe.
E) a more accurate census of the Local Group.
Continuous, Absorption Line, and Emission Line Spectra
Spectra of 3C 273
Galaxies Forming by Combining Smaller Units
Cumulative change for six personality-trait domains across the life course show distinct patterns.
Industrial and transport sources are responsible for a large proportion of global GHG emission
The results of a cytogenetic survey of over 4,000 miscarriages show a wide variation in how often sp