absolute magnitude
absolute zero
absorption lines
accretion disks
active galactic nuclei
active galaxies
active nucleus
angstroms
arc minutes
arc seconds
arms
asteroids
aurora
background radiation
barred galaxy
barred spiral galaxy
Big Bang
binary system
black dwarf
black holes
blackbody radiation
blueshifted
bremsstrahlung radiation
carbon monoxide
cD galaxies
cepheid Variables
cluster of galaxies
comets
cosmic rays
disk galaxies
Doppler shift
dust
dust lanes
dwarf irregular galaxy
E2 elliptical
electromagnetic radiation
electrons
elliptical galaxies
emission lines
emissions
false color image
far infrared
frequency
galactic disk
galaxies
galaxy cluster
gamma rays
gas
globular cluster
H alpha transition
H I
H II regions
heavy elements
helium
hydrogen
hydrogen gas
infrared
infrared emission
infrared light
infrared radiation
infrared wavelengths
intergalactic gas
intergalactic medium
interstellar dust
interstellar gas
interstellar material
interstellar medium
interstellar winds
inverse Compton emission
ionization
ionized
Irregular barred
irregular clusters
irregular galaxy
Irregular spiral
jets
Kelvin
lanes
lenticular
light
light curve
light years
Local Group
Local Supercluster
luminosity
magnetic fields
magnitudes
mass
microwave
microwave background radiation
millimeter
mixed spiral galaxy
nebulae
neutral hydrogen
neutron stars
nonthermal emissions
nuclear fusion
nuclei
open cluster
optical light
optical wavelengths
peculiar galaxy
photons
plasma
plerion
polarized
position
progenitor star
protons
protostars
pulsars
quasars
radiation
radiation pressure
radio emission
radio galaxies
radio jets
radio radiation
radio wavelengths
red giant stars
red giants
red supergiant
redshifted
remnant
RR Lyrae variables
S(B)c
S0 galaxies
S0 galaxy
Sa
Sb galaxy
Sb spiral galaxy
SBb galaxy
SBb spiral galaxy
SBcd
Sc type galaxy
Sd type spiral galaxy
Seyfert galaxies
shock front
singly ionized
solar masses
solar system
solar winds
spectral lines
spectrographic analysis
spectroscopic
spectroscopy
spectrum
speed of light
spiral arms
spiral galaxies
star clusters
starbursts
stellar winds
superclusters
supergiants
supernova remnants
supernovae
surface brightness
synchrotron emission
synchrotron radiation
T Tauri stars
thermal
thermal emission
thermal radiation
thermonuclear fusion
type "c" spiral
Type I supernova
Type II supernova
ultraviolet light
ultraviolet radiation
un-ionized
Van Allen belts
variable stars
visible light
wavelengths
white dwarfs
x-ray emission
x-ray radiation
x-ray wavelengths