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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