Widespread CO sub(2) and other non-ice compounds on the anti- Jovian and trailing sides of Europa from Galileo/NIMS observations

• Published in: Geophysical research letters Vol. 35; no. 1
• Main Authors: Hansen, Gary B, McCord, Thomas B
• Format: Journal Article
• Language: English
• Published: 01.03.2008
• ISSN: 0094-8276
• DOI: 10.1029/2007GL031748

An observation at wavelengths 0.7-5.3 [mu]m of the anti- Jovian and trailing sides of the moon Europa by the Near Infrared Mapping Spectrometer on the Galileo spacecraft has been reprocessed to reveal new details in the >3.0 [mu]m infrared spectrum. The revealed features include strong absorption bands centered at 4.25 and 4.0 [mu]m, attributed to CO sub(2) and SO sub(2), as well as weaker bands, such as near 3.5 [mu]m attributed to H sub(2)O sub(2). The calculated band depth distribution of both the CO sub(2) and SO sub(2) show that the CO sub(2) is strongly associated with the (possibly endogenic) dark (typically hydrate) regions on the surface, while the SO sub(2) is not strongly correlated with the CO sub(2), but has a similar sparse distribution. The association of CO sub(2) with the hydrates may indicate a CO sub(2)-rich ocean that is a potential environment for autotrophic organisms that might thrive near the rock-ocean interface, similar to the earliest life on Earth.