Temperature Dependence of the Water-Ice Spectrum between 1 and 4 Microns: Application to Europa, Ganymede and Saturn's Rings
Abstract
Reflection spectra of water ice from 1 to 4 μm are presented as a function of temperature. It is found that a feature at 6056 cm -1 changes its intensity sufficiently that it can be used as a spectroscopic measure of the ice temperature. A temperature calibration curve of this feature down to 55 K is developed and is used to determine ice temperatures for the Galilean satellites Europa (95±10 K), Ganymede (103±10 K), and the rings of Saturn (80±5 K). The ice temperatures for the Galilean satellites are lower than their measured brightness temperatures, which can be explained by a higher albedo of the ice covered regions relative to the rest of the satellite and possibly a concentration of the ice near the polar caps.
- Publication:
-
Icarus
- Pub Date:
- April 1975
- DOI:
- 10.1016/0019-1035(75)90058-5
- Bibcode:
- 1975Icar...24..411F
- Keywords:
-
- Astronomical Spectroscopy;
- Ice;
- Infrared Spectra;
- Planetary Temperature;
- Spectral Reflectance;
- Temperature Measurement;
- Brightness Temperature;
- Calibrating;
- Europa;
- Natural Satellites;
- Planetary Radiation;
- Polar Caps;
- Saturn Rings;
- Temperature Effects