Optical Constants of Amorphous Water Ice in the Near-Infrared
Abstract
At low temperatures and pressures pertinent to surfaces in the outer solar system water ice can exist in a number of metastable phases. The subsolar temperature range objects in the outer solar system includes the relatively balmy Galilean satellites (130-170 K), the Saturnian satellites (100-120 K), the Uranian satellites (80 K), and the frigid regions of Neptune's moon Triton (35 K), along with Pluto and its moon Charon (40 and 55 K, respectively). These temperatures suggest the ability to form various phases of water ice on these surfaces. IR transmission spectra of these various phases of water ice show that the phase transitions are accompanied by distinctive spectral changes. Because the water ice absorption features seen in the near-IR reflectance spectra of surfaces throughout the outer solar system are overtone and/or combination modes of the infrared fundamentals, they should also exhibit spectral variability that can be associated with the phase of water ice present. This would provide a mechanism of remotely recognizing these various water ice phases and thus provide information regarding the temperature history of such surfaces. Here, the optical constants of amorphous ice are presented.
- Publication:
-
Lunar and Planetary Science Conference
- Pub Date:
- March 1997
- Bibcode:
- 1997LPI....28.1199R
- Keywords:
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- Ice;
- Water;
- Amorphous Materials;
- Phase Transformations;
- Infrared Telescopes;
- Near Infrared Radiation;
- Metastable State;
- Hubble Space Telescope;
- Galileo Spacecraft;
- Lunar and Planetary Exploration;
- INDICES OF REFRACTION;
- NEAR-INFRARED OPTICAL CONSTANTS;
- OUTER SOLAR SYSTEM SURFACES;
- WATER ICE: AMORPHOUS