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Nebula
Spectroscope
Spectrum
Red/BlueShift
DopplerEffect
Big Bangtheory
Quasars
Giant stars
Supergiantstars
stars
Main sequence
(H-R) diagram
Hertzsprung-Russell
Galaxy( spiral,elliptical,inegular)
The sun
Gravity
Fusion
Corona
Chromosphere
Photosphere
Core
Prominences
Solarflares
Sunspots
Solarwind
Protostars
Neutron star or Pulsar
Supernova
Black hole
Nuclear fusion
Solarsystem
Nebular theory
Orbit
Periodof Revolution
Periodof Rotation
Inertia and Gravity
Retrograderotation
Greenhouseeffect
Planet
Asteroids/Asteroid belt
Comets/Oort Clouc
Meteors/Meteroids/Meteorites
Moon
Highlands
Maria
Craters
Rilles
Perigee
Apogee
Phasesof the Moon- ( crescent,Gibbous,waxing, waning etc.)
Eclipse
Solareclipse
Lunar eclipse
Umbra
Penumbra
Tides
Spaceage
Rockets
Reaction engines
Escapevelocity
Deep-spaceprobes
Artificial satellites
Geosynchronousorbit
Project Mercury
ProjectGemini
ProjectApollo
Skylab
Spaceshuttle
NASA
Spacestation freedom
Telescopes
Hubble Telescope