Astronomy Vocab 9

  1. Refracting Telescope
    A telescope that uses a lens to collect the light from an object.
  2. Reflecting Telescope
    A telescope that uses a mirror to collect the light from an object.
  3. Satellite
    An artificial (man-made) object or vehicle that orbits Earth, the Moon or other celestial bodies, also a celestial body that orbits another of larger size. (Moon, Earth)
  4. Solar Nebula theory
    The theory that describes how stars and planets form from contracting, spinning disks of gas and dust. 
  5. Star
    A celestial body made of hot gases, mainly hydrogen and some helium.
  6. Nebula
    A vast cloud of gas and dust, which may be the birth place of stars and planets. 
  7. Protostar
    Hot, condensed object at the centre of a nebula.
  8. Nuclear Fusion
    The process of energy production in which hydrogen nuclei combine to form helium nuclei. 
  9. Photosphere
    The surface layer of the Sun.
  10. Sunspot
    An area of strong magnetic fields on the photosphere.
  11. Solar Wind
    A stream of fast moving charged particles ejected by the Sun into the solar system.
  12. Luminosity
    A star's total energy output per second; its power in Jules per second. (J/s)
  13. Absolute Magnitude
    The magnitude of a star that we would observe if the star were placed 32.6 light years from Earth. 
  14. Spectroscope
    An optical instrument that produces a spectrum from a narrow beam of light and usually projects the spectrum into a photographic plate.
  15. Spectral Lines
    Certain specific wavelengths with a spectrum characterized by lines; spectral lines identify specific chemical elements.
  16. Hertzsprung-Russel Diagram
    A graph that compares the properties of stars.
  17. Main Sequence
    A narrow bound of stars on the H-R diagram that runs diagonally from upper left (bright, hot stars) to the lower right (low, cool stars) - Contains 90% of stars.
  18. White Dwarf
    A small dim, hot star.
  19. Supernova
    A massive explosion in which the entire outer portion of a star is blown off. 
  20. Neutron Star
    A star so dense that only neutrons can exist in its core. 
Card Set
Astronomy Vocab 9
Exploring Our Stellar Neighoorhood