Vocabulary
moon, satellite, orbit, Phases of the Moon, Lunar Phases, new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter, waning crescent, Lunar cycle (29.5 days),, solar system, gravity, nebula, mass, matter, orbit, elliptical, orbital motion, asteroid belt, planets, artificial satellites, moon, rotation, moon, stars, day/night cycle, orbit, sun, models, apparent motion, seasons, irregular, elliptical, spiral, gravity, galaxy, Milky Way, solar system, Hubble Telescope, barred spiral, reflecting, refracting, optical telescope, open cluster, globular telescope, O.B. stars, differential rotation, light year, orbit, x-ray telescope, radio telescope, solar system, gravity, nebula, mass, matter, orbit, elliptical, orbital motion, asteroid belt, planets, artificial satellites, moon, rotation, moon, stars, day/night cycle, orbit, sun, models, apparent motion, seasons, irregular, elliptical, spiral, gravity, galaxy, Milky Way, solar system, Hubble Telescope, barred spiral, reflecting, refracting, optical telescope, open cluster, globular telescope, O.B. stars, differential rotation, light year, orbit, x-ray telescope, radio telescope, rotation, moon, stars, day/night cycle, orbit, sun, models, apparent motion, seasons, irregular, elliptical, spiral, gravity, galaxy, Milky Way, solar system, Hubble Telescope, barred spiral, reflecting, refracting, optical telescope, open cluster, globular telescope, O.B. stars, differential rotation, light year, orbit, x-ray telescope, radio telescope, irregular, elliptical, spiral, gravity, galaxy, Milky Way, solar system, Hubble Telescope, barred spiral, reflecting, refracting, optical telescope, open cluster, globular telescope, O.B. stars, differential rotation, light year, orbit, x-ray telescope, radio telescope