EXAM III  Terms

Chapter 15 The Milky Way Galaxy

associations........................................Population I stars

bulge...................................................Population II stars

dark matter.........................................reddening (interstellar)

dark nebula ....................................... reflection nebula

density-wave model .......................... rotation curve

disk...................................................self-propagating star formation

emission nebulae................................spiral arms

globular clusters.................................star clusters

halo...................................................21-centimeter radiation

HII regions.........................................zone of avoidance

nucleus

open clusters

interstellar matter

 

Chapter 16 Galaxies

active galaxies.....................................poor clusters

barred spiral galaxies..........................quasars

dark matter.........................................radio galaxies

elliptical galaxies..................................recession velocity

galactic cannibalism.............................redshift

galaxy clusters.....................................rich clusters

gravitational lens.................................Seyfert galaxy

Hubble constant..................................spiral galaxies

Hubble law.........................................supercluster

irregular galaxies.................................tuning fork*

jets....................................................Virgo supercluster*

Local Group.......................................standard candles*

 

Chapter 17 Cosmology

antimatter............................................dark energy

Big Bang..............................................flat universe

cosmic horizon..................................... inflation

cosmic microwave background............. negative curvature

cosmological constant...........................Olber's paradox

cosmological principle...........................positive curvature

cosmology............................................radius of the Universe

critical density

curved space

 

Essay Three      Life in the Universe

amino acids..........................................life zone*

DNA...................................................proteins 

Drake equation*..................................SETI