Mission Information
MISSION_NAME GROUND BASED ATMOSPHERIC OBSERVATIONS
MISSION_ALIAS
MISSION_START_DATE 1993-01-01T12:00:00.000Z
MISSION_STOP_DATE 1995-01-01T12:00:00.000Z
MISSION_DESCRIPTION
Mission Overview
  ================
 
    From [KARKOSCHKA1994]
    ---------------------
      Full-disk albedo spectra of the jovian planets and Titan were
      derived from observations at the European Southern
      Observatory in July 1993.  The spectra extend from 300- to
      1000-nm wavelength at 1-nm resolution.  The signal-to-noise
      ratio is approximately 1000 in the visible.  The accuracy is
      2 percent for relative and 4 percent for absolute albedos.
      Colors and magnitudes were also determined.  Some 40-60 Raman
      scattering features are visible in the spectrum of each
      jovian planet.  A Raman scattering model with five parameters
      adjusted for each planet can explain these features.  A
      methane absorption spectrum is given which fits methane
      features in the spectra of the jovian planets and Titan.  It
      differs from room-temperature laboratory spectra but it is
      consistent with some limited laboratory data at cold
      temperatures.  Three new, weak methane bands were detected in
      the spectra of Uranus and Neptune.  A strong absorption band
      in Jupiter's spectrum is possibly due to water, confirming a
      strong depletion of oxygen in the probed part of Jupiter's
      atmosphere.
 
    From [KARKOSCHKA1998]
    ---------------------
      Full-disk albedo spectra of the jovian planets and Titan were
      derived from observations at the European Southern
      Observatory in July 1995.  The spectra extend from 300 to
      1050 nm wavelength.  The spectral resolution is 0.4 nm
      between 520 and 995 nm, and 1 nm elsewhere.  The accuracy of
      the albedo calibration is 4 percent.  UBV magnitudes were
      also determined.  Raman scattering was quantified for each
      planet.  Methane and ammonia bands are shown at 0.4 nm
      spectral resolution, including a new band at 930 nm
      wavelength which is probably due to ammonia.  Maps of the
      variation of these absorptions across the disks of Jupiter
      and Saturn are displayed.  Saturn's spectrum is undisturbed
      by light from its rings due to the edge-on geometry during
      the observations.  The albedo of Uranus near 1 micro-m
      wavelength has dropped almost 10 percent between 1993 and
      1995, while there has been no change in the ultraviolet.  The
      signature of light from Titan's surface yielded a path length
      of 4 km-am of methane in Titan's atmosphere.  The temperature
      dependence of the width of the 890-nm methane band was used
      to measure temperature variations at three altitude levels,
      resulting in the first temperature maps of Jupiter and Saturn
      based on reflected sunlight.  Jupiter displays a banded
      temperature structure with some discrete features of a few
      Kelvin amplitude.  Saturn's north-south temperature asymmetry
      has reversed since the Voyager observations.
MISSION_OBJECTIVES_SUMMARY
UNK
REFERENCE_DESCRIPTION Karkoschka, E., Spectrophotometry of the Jovian Planets and Titan at 300- to 1000-nm Wavelength: the Methane Spectrum, Icarus, 111, 174-192, 1994.

Karkoschka, E., Methane, Ammonia, and Temperature Measurements of the Jovian Planets and Titan from CCD-Spectrophotometry, Icarus, 133, 134-146, 1998.