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