J/AJ/160/282ivo://CDS.VizieR/J/AJ/160/282doi:10.26093/cds/vizier.51600282CDSTrumbo S.K.Brown M.E.Hand K.P.2021-07-05T09:04:52Z2021-03-04T07:40:29ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frsolar-systemsolar-system-planetsvisible-astronomyspectroscopyinfrared-astronomyThe composition of Europa's trailing hemisphere reflects the combined influences of endogenous geologic resurfacing and exogenous sulfur radiolysis. Using spatially resolved visible-wavelength spectra of Europa obtained with the Hubble Space Telescope, we map multiple spectral features across the trailing hemisphere and compare their geographies with the distributions of large-scale geology, magnetospheric bombardment, and surface color. Based on such comparisons, we interpret some aspects of our spectra as indicative of purely exogenous sulfur radiolysis products and other aspects as indicative of radiolysis products formed from a mixture of endogenous material and magnetospheric sulfur. The spatial distributions of two of the absorptions seen in our spectra-a widespread downturn toward the near-UV and a distinct feature at 530nm-appear consistent with sulfur allotropes previously suggested from ground-based spectrophotometry. However, the geographies of two additional features-an absorption feature at 360nm and the spectral slope at red wavelengths-are more consistent with endogenous material that has been altered by sulfur radiolysis. We suggest irradiated sulfate salts as potential candidates for this material, but we are unable to identify particular species with the available data.2020AJ....160..282Thttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/160/282CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/493/1171 : Mutual phenomena Galilean satellites PHEMU03 (Arlot+, 2009)J/A+A/532/A36 : Galilean satellites mutual events in 2009 (Zhang, 2011)J/other/SoSyR/49.383 : Galilean satellites & Jupiter pos. (Narizhnaya, 2015)J/other/SoSyR/50.344 : Galilean moons & Jupiter positions (Narizhnaya, 2016)J/other/SoSyR/52.312 : Galilean moons positions (Narizhnaya+, 2018)J/other/SoSyR/53.368 : Observations of the Galilean moons (Narizhnaya+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/160/282https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/160/282http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/160/282https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/160/282https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/160/282http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/160/282GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/AJ/160/282/fig2Representative spectrum from our HST data of the trailing hemisphere of EuroparecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWave[3e+02/1.1e+03] Wavelengthnmem.wldoubleRefl[1.1e-1/1.1] Relative reflectancephys.albedodouble