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Explore the Words

definitions & notes only words
  1. ammonia
    a pungent gas compounded of nitrogen and hydrogen (NH3)
  2. asteroid
    a small celestial body composed of rock and metal
  3. astrology
    divination by the positions of the planets and sun and moon
  4. astronomy
    the branch of physics that studies celestial bodies
  5. astrophysics
    the study of the properties of celestial bodies
  6. black hole
    a region of space resulting from the collapse of a star
  7. celestial
    relating to or inhabiting a divine heaven
  8. chromosphere
    a gaseous layer of the sun's atmosphere (extending from the photosphere to the corona) that is visible during a total eclipse of the sun
  9. comet
    a small frozen mass that travels around the sun
  10. constellation
    a configuration of stars as seen from the earth
  11. convection
    transfer of heat caused by molecular motion in liquid or gas
  12. cosmic
    pertaining to or characteristic of the universe
  13. cosmology
    metaphysical study of the origin and nature of the universe
  14. cosmos
    the universe considered as a whole
  15. Earth
    the 3rd planet from the sun; the planet we live on
  16. flare
    a burst of light used to communicate or illuminate
  17. galaxy
    a collection of star systems
  18. gravitational
    of or relating to or caused by gravitation
  19. infrared
    having or employing wavelengths longer than light but shorter than radio waves; lying outside the visible spectrum at its red end
  20. interferometer
    any measuring instrument that uses interference patterns to make accurate measurements of waves
  21. intergalactic
    existing or occuring between collections of star systems
  22. interplanetary
    between or among planets
  23. interstellar
    between or among stars
  24. Jupiter
    supreme god of Romans; counterpart of Greek Zeus
  25. leap year
    a year with 366 days that occurs every four years
  26. light year
    the distance that light travels in a vacuum in 1 year
  27. luminosity
    the quality of emitting or reflecting light
  28. Mars
    Roman god of war and agriculture
  29. Mercury
    messenger of Jupiter and god of commerce
  30. meteor
    a mass that enters earth's atmosphere, becoming incandescent
  31. meteorite
    a stony or metallic object from space that hits the earth
  32. meteoroid
    small extraterrestrial body that hits the earth's atmosphere
  33. molten
    reduced to liquid form by heating
  34. naked eye
    the eye unaided by any optical instrument that alters the power of vision or alters the apparent size or distance of objects
  35. nebula
    an immense cloud of gas and dust in interstellar space
  36. Neptune
    a giant planet with a ring of ice particles
  37. observatory
    a building equipped to view astronomical phenomena
  38. outer space
    any location outside the Earth's atmosphere
  39. photosphere
    the intensely luminous surface of a star
  40. planetarium
    an apparatus or model for representing the solar systems
  41. Pluto
    the god of the underworld in ancient mythology
  42. pseudoscience
    an activity resembling science but based on fallacious assumptions
  43. quasar
    a starlike object that may send out radio waves
  44. revolution
    a single complete turn
  45. revolve
    turn on or around an axis or a center
  46. rotation
    the act of turning as if on an axis
  47. Saturn
    god of agriculture and vegetation
  48. solar prominence
    large eruptions of luminous hydrogen gas that rise thousands of kilometers above the chromosphere
  49. stellar
    being or relating to or resembling or emanating from stars
  50. sunspot
    a cooler darker spot appearing periodically on the sun's photosphere; associated with a strong magnetic field
  51. ultraviolet
    having wavelengths shorter than light but longer than X-rays
  52. Uranus
    god of the heavens
  53. Venus
    the second nearest planet to the sun
Created on June 2, 2011

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