Download Astronomy 103 Review Sheet 3

REVIEW SHEET: ASTRON 103, PART III.
Milky Way Galaxy – structure, features:
Disk; bulge/halo; nucleus (supermassive black hole)
Location of Sun
Interstellar matter, star formation (where present/absent)
Population I, II stars: characteristics
Open, globular clusters
Turnoff point – age of star clusters
Spiral arms
Spiral Density Wave theory
Formation of Galaxy: top-down, monolithic collapse
Galaxies (formerly ‘Spiral Nebulae’)
Classification scheme (Hubble):
Ellipticals
Normal Spirals
Barred Spirals
Irregulars
Types of stars; presence/absence of interstellar matter
Rotation Curves (spiral galaxies); distribution of matter
Evidence for Dark Matter
Composition of Dark Matter
MACHOs
WIMPS
Alternate explanation(s): MOND
Galaxy Clusters; interactions
Local Group [Poor Cluster]: characteristics
Rich clusters: characteristics
Calculation of cluster mass(es): internal motions
Evidence for Dark Matter
Gravitational Lenses
Einstein’s General Theory of Relativity
Superclusters: filaments, voids
Origins in primordial density variations
Role of Dark Matter in simulations
Galaxy evolution
Mergers/acquisitions
Radio Astronomy: techniques for increasing sensitivity, resolution
Active Galaxies: definition; abundance
Light travel time determines maximum size limit
Radio Galaxies
Lobes; jets; orientations
Seyfert Galaxies
Quasars: characteristics; interpretations
Active Galactic Nuclei (AGN) – unified model:
Supermassive black holes, accretion disks, jets
Expansion of the Universe (Standard Big Bang model)
Velocity-Distance relation (Hubble’s Law)
Apparent centrality of observer(s)
Hubble’s Constant (H0)
Age of Universe = 1 / H0
Standard Big Bang theory (origin of Universe)
Cosmic Microwave Background Radiation (CMBR)
Origin (recombination after Big Bang)
Cosmological redshift
Oldest ‘picture’ of Universe
Origin of matter (nucleosynthesis) during Big Bang
Fate(s) of Universe
Open
Critical Density
Closed
Deviations from Standard Big Bang model:
Inflationary Universe
Horizon, flatness problems
Acceleration; Dark Energy
Evidence from Type Ia supernovae
Composition of Universe
Einstein’s ‘cosmological constant’ – reintroduced?