Spectral reflectance of solid sulfur trioxide (0.25-5.2 μm): Implications for Jupiter's satellite Io
Abstract
We have measured the reflection spectrum of solid sulfur trioxide and we have compared this spectrum to the spectral geometric albedo of Jupiter's satellite Io. We find that the laboratory spectrum of solid SO 3 has very strong absorption features at 3.38, and 4.08 μm. The 3.38- and 3.70-μm absorptions are present very weakly (if indeed at all) in the spectral geometric albedo of Io. This suggests that solid SO 3, if present at all, could exist only as a very minor component of Io's surface. We note that studies involving particle bombardment of SO 2 (a known Io surface constituent) produce SO 3 ( Moore, 1984, Icarus31, 40-80). Sulfur trioxide, once formed on Io's surface, would be extremely stable; however, it would not be expected to accumulate to levels detectable from Earth-based instruments. While it may be possible that the constant resurfacing of Io by volcanic ejecta may cover any SO 3 formed, the area subject to such extensive resurfacing on short time scales (∼ 1 year) is at best ∼10%. Therefore, we would expect that condensed SO 2 remote from volcanos should develop a small but significant SO 3 concentration that could be detected by instruments such as the near-infrared mapping spectrometer on the Galileo spacecraft.
- Publication:
-
Icarus
- Pub Date:
- April 1986
- DOI:
- 10.1016/0019-1035(86)90017-5
- Bibcode:
- 1986Icar...66..181N
- Keywords:
-
- Infrared Reflection;
- Io;
- Near Infrared Radiation;
- Solidified Gases;
- Spectral Reflectance;
- Sulfur Oxides;
- Ultraviolet Spectra;
- Absorption Spectra;
- Jupiter Atmosphere;
- Jupiter Satellites;
- JUPITER;
- SATELLITES;
- IO;
- REFLECTANCE;
- SPECTRA;
- SOLID PHASE;
- ALBEDO;
- SULFUR TRIOXIDE;
- COMPARISONS;
- OPTICAL PROPERTIES;
- LABORATORY STUDIES;
- ABSORPTION;
- ABUNDANCE;
- CONCENTRATION;
- SURFACE;
- RESURFACING;
- EJECTA;
- VOLCANISM;
- TIMESCALE;
- ULTRAVIOLET;
- NEAR-INFRARED;
- WAVELENGTHS