Earth and the Solar System - Middle School

Review these words related to Earth and the solar system, and you'll be a vocabulary star. Learn about the planets, different kinds of celestial bodies, gravity, eclipses, and much more. This list is out of this world!
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Full list of words from this list:

words only definitions & notes
  1. apogee
    the farthest point in an orbit around the Earth
  2. asteroid
    a small celestial body composed of rock and metal
  3. asteroid belt
    the region of interplanetary space between Mars and Jupiter where most asteroids are found
  4. atmosphere
    the envelope of gases surrounding any celestial body
  5. axis
    the center around which something rotates
  6. Big Dipper
    a group of seven bright stars in the constellation Ursa Major
  7. carbon dioxide
    a colorless, odorless greenhouse gas essential for photosynthesis
  8. Cassiopeia
    a W-shaped constellation in the northern hemisphere near Polaris
  9. celestial body
    a natural object visible in the sky
  10. Celsius scale
    a temperature scale that defines the freezing point of water as 0 degrees and the boiling point of water as 100 degrees
  11. 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
  12. comet
    a small frozen mass that travels around the sun
  13. constellation
    a configuration of stars as seen from the earth
  14. core
    the central part of the Earth
  15. corona
    the outermost region of the sun's atmosphere
  16. crater
    a depression formed by the impact of a meteorite or bomb
  17. cycle
    a periodically repeated sequence of events
  18. cyclical
    recurring in a repeated sequence of events
  19. density
    the amount per unit size
  20. direction
    relation between something and the course on which it moves
  21. distance
    the property created by the space between two objects
  22. earth
    the third planet from the sun
  23. eclipse
    the phenomenon when one celestial body obscures another
  24. ellipse
    a closed plane curve with an oval shape
  25. elliptical
    rounded like an egg
  26. energy
    any source of usable power
  27. eternity
    time without end
  28. extraterrestrial
    originating, located, or occurring outside Earth
  29. Fahrenheit
    of or relating to a temperature scale proposed by the inventor of the mercury thermometer
  30. Fahrenheit scale
    a temperature scale that defines the freezing point of water as 32 degrees and the boiling point of water a 212 degrees
  31. force
    influence that results in motion, stress, etc. when applied
  32. galaxy
    a collection of star systems
  33. Galileo Galilei
    Italian astronomer and mathematician who was the first to use a telescope to study the stars; demonstrated that different weights descend at the same rate; perfected the refracting telescope that enabled him to make many discoveries (1564-1642)
  34. gas
    state of matter distinguished from solid and liquid states
  35. gas giant
    any of the four outermost planets in the solar system
  36. geocentric
    having the earth in the middle
  37. gravitational force
    the force of attraction between all masses in the universe
  38. gravity
    the force of attraction between all masses in the universe
  39. greenhouse effect
    warming due to solar radiation trapped by the atmosphere
  40. heliocentric
    having the sun as or in the middle
  41. hemisphere
    half of the terrestrial globe
  42. inertia
    the tendency of something to stay in rest or motion
  43. Jovian planet
    any of the four outermost planets in the solar system
  44. Jupiter
    the largest planet and the 5th from the sun
  45. leap year
    a year with 366 days that occurs every four years
  46. Leo
    a zodiacal constellation in northern hemisphere between Cancer and Virgo
  47. light year
    the distance that light travels in a vacuum in 1 year
  48. Little Dipper
    a cluster of seven stars in Ursa Minor
  49. lunar
    of or relating to or associated with the moon
  50. magnetic field
    the lines of force surrounding a permanent magnet or a moving charged particle
  51. Mars
    a small reddish planet that is the 4th from the sun and is periodically visible to the naked eye; minerals rich in iron cover its surface and are responsible for its characteristic color
  52. mass
    the property of a body that causes it to have weight
  53. Mercury
    the smallest planet and the nearest to the sun
  54. meteor
    a mass that enters earth's atmosphere, becoming incandescent
  55. meteorite
    a stony or metallic object from space that hits the earth
  56. meteoroid
    a small piece of rock or metal moving through outer space
  57. meteor shower
    a transient shower of meteors when a meteor swarm enters the earth's atmosphere
  58. Milky Way
    the galaxy containing the solar system
  59. month
    one of the twelve divisions of the calendar year
  60. moon
    the natural satellite of the Earth
  61. NASA
    an independent agency of the United States government responsible for aviation and spaceflight
  62. nebula
    an immense cloud of gas and dust in interstellar space
  63. Neptune
    a giant planet with a ring of ice particles
  64. Nicolaus Copernicus
    Polish astronomer who produced a workable model of the solar system with the sun in the center (1473-1543)
  65. nitrogen
    a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues
  66. North Star
    the brightest star in Ursa Minor
  67. nuclear fusion
    a nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy
  68. Oort cloud
    (astronomy) a hypothetical huge collection of comets orbiting the sun far beyond the orbit of Pluto; perturbations (as by other stars) can upset a comet's orbit and may send it tumbling toward the sun
  69. orbit
    the path of a celestial body in its revolution about another
  70. Orion
    a constellation on the equator to the east of Taurus
  71. outer planet
    a major planet whose orbit is outside the asteroid belt
  72. oxygen
    a colorless, odorless gas that is essential for respiration
  73. Pegasus
    a constellation in the northern hemisphere near Andromeda and Pisces
  74. phase
    the particular appearance of a body's state of illumination
  75. photosphere
    the intensely luminous surface of a star
  76. photosynthesis
    formation of compounds in plants aided by radiant energy
  77. planet
    a celestial body that revolves around the sun
  78. planetesimal
    one of many small solid celestial bodies thought to have existed at an early stage in the development of the solar system
  79. Pluto
    a dwarf planet with an elliptical orbit
  80. pole
    either of the two endpoints of the Earth's axis of rotation
  81. Ptolemy
    Alexandrian astronomer (of the 2nd century) who proposed a geocentric system of astronomy that was undisputed until the late Renaissance
  82. reflection
    the phenomenon of a wave being thrown back from a surface
  83. retrograde
    move backward in an orbit, of celestial bodies
  84. revolution
    a single complete turn
  85. ring
    a toroidal shape
  86. rotation
    the act of turning as if on an axis
  87. satellite
    any celestial body orbiting around a planet or star
  88. Saturn
    a giant planet that is surrounded by three planar concentric rings of ice particles; the 6th planet from the sun
  89. scale
    an ordered reference standard
  90. season
    one of the natural periods into which the year is divided by the equinoxes and solstices or atmospheric conditions
  91. solar
    relating to the sun or utilizing the energies of the sun
  92. solar eclipse
    when the moon interrupts light from the sun
  93. solar flare
    a sudden eruption of intense high-energy radiation from the sun's surface; associated with sunspots and radio interference
  94. solar system
    the sun with the celestial bodies that revolve around it
  95. solar wind
    a stream of protons moving radially from the sun
  96. space
    any location outside the Earth's atmosphere
  97. space probe
    a rocket-propelled guided missile that can escape the earth's atmosphere; makes observations of the solar system that cannot be made by terrestrial observation
  98. space shuttle
    a reusable spacecraft with wings for a controlled descent through the Earth's atmosphere
  99. space station
    a manned artificial satellite in a fixed orbit designed for scientific research
  100. speed of light
    the speed at which light travels in a vacuum
  101. star
    a celestial body of hot gases that radiates energy
  102. stationary
    standing still
  103. Sun
    the star that is the source of light and heat for the planets in the solar system
  104. sunspot
    a cooler darker spot appearing periodically on the sun's photosphere; associated with a strong magnetic field
  105. surface
    the two-dimensional boundary of a three-dimensional object
  106. telescope
    a magnifier of images of distant objects
  107. terrestrial
    of or relating to or characteristic of the planet Earth
  108. terrestrial planet
    a planet having a compact rocky surface like the Earth's
  109. tide
    the periodic rise and fall of the sea level
  110. tilt
    property possessed by a line that departs from the vertical
  111. universe
    everything that exists anywhere
  112. Uranus
    a giant planet with a ring of ice particles
  113. Ursa Major
    a constellation outside the zodiac that rotates around the North Star
  114. Ursa Minor
    a constellation outside the zodiac that rotates around the North Star
  115. Venus
    the second nearest planet to the sun
  116. weight
    the vertical force exerted by a mass as a result of gravity
  117. year
    the period of time that it takes for a planet (as, e.g., Earth or Mars) to make a complete revolution around the sun
Created on Thu Feb 02 16:58:03 EST 2017 (updated Tue Apr 18 09:20:23 EDT 2017)

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