The Universe and Its Stars (Cosmology) - Middle School

You'll have a stellar vocabulary once you review this list of of terms related to cosmology. Expand your knowledge of the universe as you learn about galaxies, constellations, and the solar system. Reach for the stars!
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Full list of words from this list:

words only definitions & notes
  1. absolute magnitude
    (astronomy) the magnitude that a star would have if it were viewed from a distance of 10 parsecs (32.62 light years) from the earth
  2. Albert Einstein
    physicist born in Germany who formulated the special theory of relativity and the general theory of relativity; Einstein also proposed that light consists of discrete quantized bundles of energy (later called photons) (1879-1955)
  3. asteroid
    a small celestial body composed of rock and metal
  4. astronomy
    the branch of physics that studies celestial bodies
  5. atom
    the smallest component of an element
  6. big bang theory
    (cosmology) the theory that the universe originated sometime between 10 billion and 20 billion years ago from the cataclysmic explosion of a small volume of matter at extremely high density and temperature
  7. black hole
    a region of space resulting from the collapse of a star
  8. Christian Johann Doppler
    Austrian physicist famous for his discovery of the Doppler effect (1803-1853)
  9. closed universe
    (cosmology) a universe that is spatially closed and in which there is sufficient matter to halt the expansion that began with the big bang; the visible matter is only 10 percent of the matter required for closure but there may be large amounts of dark matter
  10. comet
    a small frozen mass that travels around the sun
  11. constellation
    a configuration of stars as seen from the earth
  12. corona
    the outermost region of the sun's atmosphere
  13. cosmic background radiation
    (cosmology) the cooled remnant of the hot big bang that fills the entire universe and can be observed today with an average temperature of about 2.725 kelvin
  14. cosmology
    the study of the evolution and structure of the universe
  15. cosmos
    the universe considered as a whole
  16. dark matter
    a hypothetical invisible form of matter making up most of the universe
  17. debris
    the remains of something that has been destroyed
  18. density
    the amount per unit size
  19. eclipse
    the phenomenon when one celestial body obscures another
  20. Edwin Hubble
    United States astronomer who discovered that (as the universe expands) the speed with which nebulae recede increases with their distance from the observer (1889-1953)
  21. electromagnetic spectrum
    the entire frequency range of electromagnetic waves
  22. electromagnetism
    a physical force produced from the interaction of charged particles
  23. electron
    an elementary particle with negative charge
  24. element
    a substance that cannot be separated into simpler substances
  25. emission
    the act of causing to flow forth
  26. energy
    any source of usable power
  27. frequency
    the number of occurrences within a given time period
  28. fusion
    reaction in which nuclei combine to form more massive nuclei
  29. galaxy
    a collection of star systems
  30. 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)
  31. geocentric
    having the earth in the middle
  32. gravity
    the force of attraction between all masses in the universe
  33. heliocentric
    having the sun as or in the middle
  34. helium
    a light colorless element that is one of the six inert gases
  35. hydrogen
    a colorless, odorless gas; the lightest chemical element
  36. Hypatia
    Greek philosopher and astronomer; she invented the astrolabe
  37. hypothesis
    a tentative insight that is not yet verified or tested
  38. interstellar
    between or among stars
  39. iron
    a heavy ductile magnetic metallic element
  40. Isaac Newton
    English mathematician and physicist
  41. isotope
    atom with same atomic number, different number of neutrons
  42. Johannes Kepler
    German astronomer who first stated laws of planetary motion
  43. lifespan
    the period during which a person, animal, or object exists
  44. light
    electromagnetic radiation that can produce visual sensation
  45. light year
    the distance that light travels in a vacuum in 1 year
  46. luminous
    softly bright or radiant
  47. magnetic field
    the lines of force surrounding a permanent magnet or a moving charged particle
  48. mass
    the property of a body that causes it to have weight
  49. matter
    that which has mass and occupies space
  50. meteor
    a mass that enters earth's atmosphere, becoming incandescent
  51. meteorite
    a stony or metallic object from space that hits the earth
  52. microwave
    a relatively short electromagnetic wave used for cooking food
  53. Milky Way
    the galaxy containing the solar system
  54. momentum
    the product of a body's mass and its velocity
  55. nebula
    an immense cloud of gas and dust in interstellar space
  56. neutron star
    a star that has collapsed under its own gravity
  57. Nicolaus Copernicus
    Polish astronomer who produced a workable model of the solar system with the sun in the center (1473-1543)
  58. nova
    a star that ejects some of its material in the form of a cloud and become more luminous in the process
  59. nuclear fusion
    a nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy
  60. nucleus
    the positively charged dense center of an atom
  61. orbit
    the path of a celestial body in its revolution about another
  62. parallax
    apparent displacement of an object as seen from two points
  63. particle
    a body having finite mass but negligible dimensions
  64. phase
    the particular appearance of a body's state of illumination
  65. planet
    a celestial body that revolves around the sun
  66. planetesimal
    one of many small solid celestial bodies thought to have existed at an early stage in the development of the solar system
  67. plasma
    a fourth state of matter distinct from solid, liquid or gas
  68. primordial
    having existed from the beginning
  69. proton
    a stable particle with positive charge
  70. Ptolemy
    Alexandrian astronomer (of the 2nd century) who proposed a geocentric system of astronomy that was undisputed until the late Renaissance
  71. pulsar
    a degenerate neutron star that emits polarized radiation
  72. quasar
    a starlike object that may send out radio waves
  73. radiant energy
    energy that is transmitted in the form of radiation
  74. radiation
    energy transmitted in the form of rays or waves or particles
  75. radio telescope
    astronomical telescope that picks up electromagnetic radiations in the radio-frequency range from extraterrestrial sources
  76. red giant
    a large, old, luminous star
  77. reflecting telescope
    optical telescope consisting of a large concave mirror that produces an image that is magnified by the eyepiece
  78. solar flare
    a sudden eruption of intense high-energy radiation from the sun's surface; associated with sunspots and radio interference
  79. solar system
    the sun with the celestial bodies that revolve around it
  80. space
    any location outside the Earth's atmosphere
  81. space-time
    the four-dimensional coordinate system (3 dimensions of space and 1 of time) in which physical events are located
  82. spectroscope
    an optical instrument for spectrographic analysis
  83. spectroscopy
    the use of spectroscopes to analyze spectra
  84. spectrum
    an ordered array of the components of an emission or wave
  85. spiral galaxy
    a large system of stars arranged in a curved pattern around a center
  86. star
    a celestial body of hot gases that radiates energy
  87. stellar
    being or relating to or resembling or emanating from stars
  88. Stephen Hawking
    English theoretical physicist (born in 1942)
  89. sunspot
    a cooler darker spot appearing periodically on the sun's photosphere; associated with a strong magnetic field
  90. supergiant
    an extremely bright star of very large diameter and low density
  91. supernova
    a star that explodes and becomes luminous in the process
  92. system
    a group of independent elements comprising a unified whole
  93. telescope
    a magnifier of images of distant objects
  94. theory
    a well-substantiated explanation of some aspect of the world
  95. time
    the continuum of experience in which events pass to the past
  96. universe
    everything that exists anywhere
  97. vacuum
    the absence of matter
  98. visible light
    (physics) electromagnetic radiation that can produce a visual sensation
  99. wave
    (physics) a movement up and down or back and forth
  100. wavelength
    distance between successive crests of a periodic disturbance
  101. white dwarf
    a faint star of enormous density
  102. zenith
    the highest point of something
Created on Fri Feb 10 20:22:09 EST 2017 (updated Mon Apr 17 17:11:59 EDT 2017)

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