| Popis: |
On 29 September 2022 Juno’s low-light Stellar Reference Unit (SRU) captured a high-resolution image (256-340 m/pixel) of a 3x104 km2 region of Europa’s surface between ~0-6°N and 43.5-51°W. The broadband visible image (450-1100 nm), with the highest resolution ever for that region, was collected at a sub-spacecraft altitude of 412 km during Juno’s close flyby of the icy Jovian moon while the surface was illuminated only by Jupiter-shine (incidence angle: 48-51 degrees). Prior coverage of the area by Galileo was under high-sun conditions at 1 km resolution, leading to characterization of the region as mostly ridged plain and undifferentiated linea. The SRU image reveals a much richer and complex picture; an intricate network of cross-cutting ridges and lineated bands interrupted by an intriguing 37 km (east-west) by 67 km (north-south) chaos feature that appears to be the result of a unique, local geologic process. Low-albedo deposits flank ridges near the chaos feature and bear similarity to features previously linked to hypothesized subsurface activity [Quick & Hedman, Icarus, 2020]. We will present updates to the geologic mapping of Europa enabled by the SRU image, our study of the chaos feature’s morphology, and puzzles awaiting future high-resolution imagery from Europa Clipper or JUICE. The JPL authors’ copyright for this abstract is held by the California Institute of Technology. Government Sponsorship acknowledged. |
