Astronomy 1

  1. Equant
    In the Ptolemaic theory, the point off center in the deferent from which the center of the epicycle appears to move uniformly
  2. Wavelength
    Inversely related to the energy of a photon
  3. Focal Length
    The distance between an objective and its focused image of a very distant object
  4. Objective
    The lens or mirror that first produces a focused image as opposed to modifying, enlarging or redirecting the image
  5. Prime Focus
    The point at which the objective mirror forms an image
  6. Cassegrain focus
    A focus location directly beneath the objective mirror
  7. Newtonian focus
    a focus location at the upper side of a telescope
  8. equatorial mounting
    mounting in which one axis points to a celestial pole
  9. Alt-azimoth mounting
    Mounting in which one axis points vertically upward
  10. light gathering power
    the ability of a telescope to reveal fine detail
  11. angstrom
    a unit of distance equaling 10 to the negative 10 meters
  12. comparison spectrum
    a spectrum of known spectral lines used to identify unknown wavelengths in an objects spectrum. This helps identify the fingerprint of the source
  13. polar axis
    In an equatorial telescope mounting the axis that is parallel to earth's axis
  14. schmidt-Cassegrain focus
    The optical design that uses a thin corrector plate at the entrance to the telescope tube
  15. synodic month
    the period of the phases of the moon
  16. sidereal period
    The time a celestial body takes to turn once on its axis or revolve once around the sun
  17. synodic period
    An objects orbital period with respect to the sun
  18. aphelion
    The orbital point of greatest distance from the sun
  19. apogee
    The point farthest from Earth in the orbit of a body circling Earth
  20. Corona
    On the sun, the faint outer atmosphere composed of low-density high temperature gas
  21. Saros cycle
    An 18 year, 11 day period after which the pattern of lunar and solar eclipses repeats
  22. nodes
    The points where an objects orbit passes through the plane of Earth's orbit
  23. parallax
    The apparent change in the observed position of an object due to change in the location of the observer
  24. epicycle
    in the Ptolemaic theory a small circle in which a planet moves
  25. deferent
    In the Ptolemaic theory, a large circle around Earth along which the center of the epicycle moved
  26. perigee
    the piont closest to earth in the orbit of a body circling Earth
  27. Photosphere
    The bright visible surface of the sun
Card Set
Astronomy 1
Astronomy test 1