Salts and organics on Ganymede’s surface observed by the JIRAM spectrometer onboard Juno
Journal
Date Issued
2024
Author(s)
•
•
•
•
Glein, Christopher R.
•
•
Lunine, Jonathan I.
•
•
•
•
•
Bolton, Scott J.
•
Hansen, Candice J.
•
Nordheim, Tom A.
•
•
•
•
Brooks, Shawn M.
•
•
Dinelli, Bianca Maria
•
•
•
•
•
•
•
•
Abstract
The surface of Ganymede exhibits diversity in composition, interpreted as indicative of geological age differences between dark and bright terrains. Observations from Galileo and Earth-based telescopes have revealed the presence of both water ice and non-ice material, indicative of either endogenic or exogenic processes, or some combination. However, these observations attained a spatial resolution that was too coarse to reveal the surface composition at a local scale. Here we present the high-spatial-resolution infrared spectra of Ganymede observed with the Jovian InfraRed Auroral Mapper onboard the National Aeronautics and Space Administration’s Juno spacecraft during a close flyby that occurred on 7 June 2021. We found that at a pixel resolution <1 km, the surface of Ganymede exhibits signatures diagnostic of hydrated sodium chloride, ammonium chloride and sodium/ammonium carbonate, as well as organic compounds, possibly including aliphatic aldehydes. Carbon dioxide shows up mostly at trailing longitudes. The composition and spatial distribution of these salts and organics suggest that their origin is endogenic, resulting from the extrusion of subsurface brines, whose chemistry reflects the water–rock interaction inside Ganymede.
Volume
8
Issue
1
Start page
82
Issn Identifier
2397-3366
Ads BibCode
2024NatAs...8...82T
Rights
restricted
File(s)![Thumbnail Image]()
![Thumbnail Image]()
Loading...
Name
NatureAstronomy_manuscript_JIRAM_Tosi_v4.0_clean-1.pdf
Description
Preprint
Size
366.18 KB
Format
Adobe PDF
Checksum (MD5)
0b9e056656cd9976afa2932fbf28ea52
Loading...
Name
200_Tosi_NatAstron_2024.pdf
Description
[Administrators only]
Size
2.9 MB
Format
Adobe PDF
Checksum (MD5)
13f1eae4ef0a0b72082d437409e48148
