Articles | Volume 44, issue 2
https://doi.org/10.5194/angeo-44-1093-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/angeo-44-1093-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
15 Oct 2026
Regular paper |
| 15 Oct 2026
| 15 Oct 2026
Ultraviolet observations of the Earth and Moon during the JUICE Lunar-Earth flyby
Southwest Research Institute, San Antonio, Texas, USA
Michael W. Davis
Southwest Research Institute, San Antonio, Texas, USA
Rohini S. Giles
Southwest Research Institute, San Antonio, Texas, USA
Thomas K. Greathouse
Southwest Research Institute, San Antonio, Texas, USA
Kurt D. Retherford
Southwest Research Institute, San Antonio, Texas, USA
Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, Texas, USA
Maarten H. Versteeg
Southwest Research Institute, San Antonio, Texas, USA
Sue A. Ferrell
Southwest Research Institute, San Antonio, Texas, USA
Tracy M. Becker
Southwest Research Institute, San Antonio, Texas, USA
Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, Texas, USA
G. Randall Gladstone
Southwest Research Institute, San Antonio, Texas, USA
Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, Texas, USA
Bradley J. Trantham
Southwest Research Institute, San Antonio, Texas, USA
Joshua A. Kammer
Southwest Research Institute, San Antonio, Texas, USA
Matthew A. Freeman
Southwest Research Institute, San Antonio, Texas, USA
Steven C. Persyn
Southwest Research Institute, San Antonio, Texas, USA
Cited articles
Alday, J., Roth, L., Ivchenko, N., Retherford, K. D., Becker, T. M., Molyneux, P., and Saur, J.: New constraints on Ganymede's hydrogen corona: Analysis of Lyman-α emissions observed by HST/STIS between 1998 and 2014, Planet. Space Sci., 148, 35–44, https://doi.org/10.1016/j.pss.2017.10.006, 2017.
Baliukin, I. I., Bertaux, J. L., Quémerais, E., Izmodenov, V. V., and Schmidt, W.: SWAN/SOHO Lyman‐α mapping: The hydrogen geocorona extends well beyond the Moon, J. Geophys. Res.-Space Phys., 124, 861–885, https://doi.org/10.1029/2018JA026136, 2019.
Barth, C. A., Hord, C. W., Stewart, A. I. F., Pryor, W. R., Simmons, K. E., McClintock, W. E., Ajello, J. M., Naviaux, K. L., and Aiello, J. J.: Galileo ultraviolet spectrometer observations of atomic hydrogen in the atmosphere of Ganymede, Geophys. Res. Lett., 24, 2147–2150, https://doi.org/10.1029/97GL01927, 1997.
Bertaux, J.-L.: Interpretation of OGO-5 line shape measurements of Lyman-alpha emission from terrestrial exospheric hydrogen, Planet. Space Sci., 26, 431–447, https://doi.org/10.1016/0032-0633(78)90065-X, 1978.
Byron, B. D., Retherford, K. D., Greathouse, T. K., Wyrick, D., Cahill, J. T. S., Hendrix, A. R., Raut, U., Mandt, K. E., and Denevi, B. W.: Far‐UV observations of lunar rayed craters with LRO‐LAMP, J. Geophys. Res.-Planets, 125, e2019JE006269, https://doi.org/10.1029/2019JE006269, 2020.
Cunningham, N. J., Spencer, J. R., Feldman, P. D., Strobel, D. F., France, K., and Osterman, S. N.: Detection of Callisto's oxygen atmosphere with the Hubble Space Telescope, Icarus, 254, 178–189, https://doi.org/10.1016/j.icarus.2015.03.021, 2015.
Czajka, E., Retherford, K., Kramer, G., Hendrix, A., Cahill, J., Byron, B., Greenhagen, B., Greathouse, T., Magaña, L., Mandt, K., and Grava, C.: New Insights into Aristarchus Crater with LRO LAMP Far-ultraviolet Observations, Planet. Sci. J., 4, 137, https://doi.org/10.3847/PSJ/acdee9, 2023.
Davis, M. W., Gladstone, G. R., Greathouse, T. K., Slater, D. C., Versteeg, M. H., Persson, K. B., Winters, G. S., Persyn, S, C., and Eterno, J. S.: Radiometric performance results of the Juno ultraviolet spectrograph (Juno-UVS), Proc. SPIE 8146, UV/Optical/IR Space Telescopes and Instruments: Innovative Technologies and Concepts V, 814604, https://doi.org/10.1117/12.894274, 2011.
Davis, M. W., Siegmund, O. H. W., Gladstone, G. R., Martin, A., Molyneux, P. M., Retherford, K. D., Veach, T. J., and Vallerga, J. V.: Bench and thermal vacuum testing of the JUICE-UVS microchannel plate detector system, Proc. SPIE 11118, UV, Ex-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXI, 111180Q, https://doi.org/10.1117/12.2529649, 2019.
Davis, M. W., Gladstone, G. R., Giles, R. S., Greathouse, T. K., Molyneux, P. M., Raut, U., Retherford, K. D., Baldor, S., Versteeg, M. H., Freeman, M., Persson, K., and Persyn, S. C.: Ground calibration results of the JUICE ultraviolet spectrograph, Proc. SPIE 11444, Space Telescopes and Instrumentation 2020: Ultraviolet to Gamma Ray, 1144404, https://doi.org/10.1117/12.2562986, 2020.
Davis, M. W., Gladstone, G. R., Greathouse, T. K., Molyneux, P. M., Retherford, K. D., Ferrell, S. A., Versteeg, M. H., and Persyn, S. C.: Results of the JUICE ultraviolet spectrograph near-Earth commissioning, Proc. SPIE 13093, Space Telescopes and Instrumentation 2024: Ultraviolet to Gamma Ray, 1309305, https://doi.org/10.1117/12.3020022, 2024.
Davis, M. W., Giles, R. S., Greathouse, T. K., Molyneux, P. M., Ferrell, S. A., Versteeg, M. H., Gladstone, G. R., Retherford, K. D., Trantham, B. J., Freeman, M. A., and Persyn, S. C.: Jupiter icy moons explorer ultraviolet spectrograph: results from payload checkouts 1 and 2 and the lunar-Earth gravity assist maneuver, Proc. SPIE 13625, UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXIV, 1362508, https://doi.org/10.1117/12.3063995, 2025.
Denk, T., Williams, D. A., Tosi, F., Bell, J. F., Mottola, S., de Pater, I., Lainey, V., Molyneux, P., Matz, K.-D., Hartogh, P. Lopes, R. M., Solomonidou, A., Thomas, P. C., Huybrighs, H. L. F., Gurvits, L. I., Mura, A., Retherford, K. D., Rezac, L., Roatsch, T., Roth, L., Haslebacher, N., Tubiana, C., Lucchetti, A., Langevin, Y., Poulet, F., Lellouch, E., Tsuchiya, F., Vallat, C., Van Hoolst, T., Vorburger, A., Wurz, P., D’Aversa, E., Gladstone, R., Greathouse, T., Schneider, N., Zambon, F., Altobelli, N., Palumbo, P., Portyankina, G., Aharonson, O., Bruzzone, L., Carter, J., Cecconi, B., Cooper, N., Costa Sitjà, M., Escalante López, A., Futaana, Y., Mazzotta Epifani, E., Migliorini, A., Moore, W. B., Moreno, R., Murray, C., Penasa, L., Piccioni, G., Schmidt, J., Wahlund, J.-E., and Witasse, O.: Io and the Minor Jovian Moons – Prospects for JUICE, Space Sci. Rev., 222, 27, https://doi.org/10.1007/s11214-025-01263-6, 2026.
European Space Agency: ESA-JUICE_LEGA-Special-Issue_v1.0, European Space Agency [data set], https://doi.org/10.57780/esa-2bb387d, 2026.
Feldman, P. D., McGrath, M. A., Strobel, D. F., Moos, H. W., Retherford, K. D., and Wolven, B. C.: HST/STIS ultraviolet imaging of polar aurora on Ganymede, Astrophys. J., 535, 1085–1090, https://doi.org/10.1086/308889, 2000.
Fletcher, L. N., Cavalié, T., Grassi, D., Hueso, R., Lara. L. M.,Kaspi, Y., Galanti, E., Greathouse, T. K., Molyneux, P. M., Galand, M., Vallat, C., Witasse, O., Lorente, R., Hartogh, P., Poulet, F., Langevin, Y., Palumbo, P., Gladstone, G. R., Retherford, K. D., Dougherty, M. K., Wahlund, J.-E., Barabash, S., Iess, L., Bruzzone, L., Hussmann, H., Gurvits, L. I., Santolik, O., Kolmasova, I., Fischer, G., Müller-Wodarg, I., Piccioni, G., Fouchet, T., Gérard, J.-C., Sánchez-Lavega, A., Irwin, P. G. J., Grodent, D., Altieri, F., Mura, A., Drossart, P., Kammer, J., Giles, R., Cazaux, S., Jones, G., Smirnova, M., Lellouch, E., Medvedev, A. S., Moreno, R., Rezac, L., Coustenis, A., and Costa, M.: Jupiter Science Enabled by ESA's Jupiter Icy Moons Explorer, Space Sci. Rev., 219, https://doi.org/10.1007/s11214-023-00996-6, 2023.
Gladstone, G. R.: Simulations of DE 1 UV airglow images, J. Geophys. Res., 99, 11441–11448, https://doi.org/10.1029/93JA03525, 1994.
Gladstone, G. R., Stern, S. A., Retherford, K. D., Black, R. K., Slater, D. C., Davis, M. W., Versteeg, M. H., Persson, K. B., Parker, J. W., Kaufmann, D. E., Egan, A. F., Greathouse, T. K., Feldman, P. D., Hurley, D., Pryor W. R., and Hendrix, A. R.: LAMP: the Lyman alpha mapping project on NASA's Lunar reconnaissance orbiter mission, Space Sci. Rev., 150, 161–181, https://doi.org/10.1007/s11214-009-9578-6, 2010.
Gladstone, G. R., Persyn, S. C., Eterno, J. S., Walther, B. C., Slater, D. C., Davis, M. W., Versteeg, M. H., Persson, K. B., Young, M. K., Dirks, G. J., Sawka, A. O., Tumlinson, J., Sykes, H., Beshears, J., Rhoad, C. L., Cravens, J. P., Winters, G. S., Klar, R. A., Lockhart, W., Piepgrass, B. M., Greathouse, T. K., Trantham, B. J., Wilcox, P. M., Jackson, M. W., Siegmund, O. H. W., Vallerga, J. V., Raffanti, R., Martin, A., Gérard, J.-C., Grodent, D. C., Bonfond, B., Marquet, B., and Denis, F.: The ultraviolet spectrograph on NASA's Juno mission, Space Sci. Rev., 213, 447–473, https://doi.org/10.1007/s11214-014-0040-z, 2017.
Greathouse, T. K., Gladstone, G. R., Molyneux, P. M., Versteeg, M. H., Hue, V., Kammer, J. A., Davis, M. W., Bolton, S. J., Giles, R. S., Connerney, J. E. P., and Gerard, J.-C.: UVS observations of Ganymede's aurora during Juno orbits 34 and 35, Geophys. Res. Lett., 49, e2022GL099794, https://doi.org/10.1029/2022GL099794, 2022.
Kanik, I., Noren, C., Makarov, O. P., Vattipalle, P., Ajello, J. M., and Shemansky, D. E.: Electron impact dissociative excitation of O2: 2. Absolute emission cross sections of the OI (130.4 nm) and OI (135.6 nm) lines, J. Geophys. Res.-Planets, 108, https://doi.org/10.1029/2000JE001423, 2003.
McGrath, M. A., Jia, X., Retherford, K., Feldman, P. D., Strobel, D. F., and Saur, J.: Aurora on Ganymede, J. Geophys. Res.-Space Phys., 118, 2043–2054, https://doi.org/10.1002/jgra.50122, 2013.
Meier, R. R.: Ultraviolet spectroscopy and remote sensing of the upper atmosphere, Space Sci. Rev., 58, 1–185, https://doi.org/10.1007/BF01206000, 1991.
Molyneux, P. M., Greathouse, T. K., Gladstone, G. R., Versteeg, M. H., Hue, V., Kammer, J., Davis, M. W., Bolton, S. J., Giles, R., Connerney, J. E. P., and Gérard, J.-C.: Ganymede's UV reflectance from Juno‐UVS data, Geophys. Res. Lett., 49, e2022GL099532, https://doi.org/10.1029/2022GL099532, 2022.
Paxton, L. J., Christensen, A. B., Humm, D. C., Ogorzalek, B. S., Pardoe, C. T., Morrison, D., Weiss, M. B., Crain, W., Lew, P. H., Mabry, D. J., and Goldsten, J. O.: Global ultraviolet imager (GUVI): Measuring composition and energy inputs for the NASA Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) mission, Proc. SPIE 3756, Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, https://doi.org/10.1117/12.366380, 1999.
Retherford, K. D., Becker, T. M., Gladstone, G. R., Greathouse, T.K., Davis, M. W., Velez, M. A., Freeman, M. A., Brooks, S. M., Ferrell, S., Giles, R. S., Hendrix, A. R., Hue, V., Johnson, E., Kammer, J. A., Marinan, A. D., Mamo, B. D., McGrath, M. A., Molyneux, P. M., Nerney, E. G., Perez, B., Persson, K. B., Pope, S., Raut, U., Rickerson, R., Roth, L., Saur, J., Siegmund, O. H. W, Spencer, J. R., Steffl, A. J., Stern, S. A., Trantham, B. J., Versteeg, M. H., Winkenstern, J., and the Europa-UVS Team: Europa Ultraviolet Spectrograph (Europa-UVS), Space Sci. Rev., 220, 89, https://doi.org/10.1007/s11214-024-01121-x, 2024.
Retherford, K. D., Molyneux, P. M., Greathouse, T. K., Davis, M. W., Gladstone, G. R., Persyn, S. C., Versteeg, M. H., Araujo, M. F., Bagenal, F., Becker, T. M. Beth, A., Black, R. K., Bonfond, B., Brooks, S. M., Bunce, E. J., Carapelle, A., Cortinas, S., Dirks, G. J., Esquivel, B., Feldman, P. D., Ferrell, S., Ferris, M., Fletcher, L. N., Freeman, M. A., Galand, M., Giles, R. S., Grodent, D., Hue, V., Johnson, E., Kammer, J. A., Kempe, C., Lamy, L., Martin, A., McGrath, M. A., Nerney, E. G., Nuñez, C., Olsen, Z., Pelletier, N., Perez, B., Persson, K. B., Quémerais, E., Raffanti, R., Raut, U., Rickerson, R., Roth, L., Siegmund, O. H. W., Spencer, J. R., Steffl, A. J., Trantham, B. J., Vallerga, J. V., Veach, T. J., Velez, M. A., Walther, B. C., and the JUICE-UVS Team: The Ultraviolet Spectrograph on ESA's Jupiter Icy Moons Explorer Mission (JUICE-UVS), arXiv [preprint], https://arxiv.org/abs/2609.02856, 2 September 2026.
Roth, L.: A stable H2O atmosphere on Europa's trailing hemisphere from HST images, Geophys. Res. Lett., 48, e2021GL094289, https://doi.org/10.1029/2021GL094289, 2021.
Roth, L., Saur, J., Retherford, K. D., Strobel, D. F., Feldman, P. D., McGrath, M. A., Spencer, J. R., Blöcker, A., and Ivchenko, N.: Europa's far ultraviolet oxygen aurora from a comprehensive set of HST observations, J. Geophys. Res.-Space Phys., 121, 2143–2170, https://doi.org/10.1002/2015JA022073, 2016.
Roth, L., Ivchenko, N., Gladstone, G. R., Saur, J., Grodent, D., Bonfond, B., Molyneux, P. M., and Retherford, K. D.: A sublimated water atmosphere on Ganymede detected from Hubble Space Telescope observations, Nat. Astron., 5, 1043–1051, https://doi.org/10.1038/s41550-021-01426-9, 2021.
Siegmund, O. H. W., McPhate, J. B., Jelinsky, S. R., Vallerga, J. V., Tremsin, A. S., and Hemphill, R.: Large area microchannel plate imaging counting detectors with sub-nanosecond timing, IEEE T. Nucl. Sci., 60, 923–931, https://doi.org/10.1109/TNS.2013.2252364, 2013.
Slater, D. C., Davis, M. W., Olkin, C. B., Scherrer, J., and Stern, S. A.: Radiometric performance results of the New Horizons' ALICE UV imaging spectrograph. Proc. SPIE 5906, Astrobiology and Planetary Missions, 590619, https://doi.org/10.1117/12.613127, 2005.
Stern, S. A., Slater, D. C., Scherrer, J., Stone, J., Versteeg, M., A'Hearn, M. F., Bertaux, J. L., Feldman, P. D., Festou, M. C., Parker, J. W., and Siegmund, O. H. W.: Alice: the Rosetta ultraviolet imaging spectrograph, Space Sci. Rev., 128, 507–527, https://doi.org/10.1007/s11214-006-9035-8, 2007.
Stern, S. A., Slater, D. C., Scherrer, J., Stone, J., Dirks, G., Versteeg, M., Davis, M., Gladstone, G. R., Parker, J. W., Young, L. A., and Siegmund, O. H. W.: ALICE: The ultraviolet imaging spectrograph aboard the New Horizons Pluto–Kuiper Belt mission, Space Sci. Rev., 140, 155–187, https://doi.org/10.1007/s11214-008-9407-3, 2008.
Tosi, F., Roatsch, T., Galli, A., Hauber, E., Lucchetti, A., Molyneux, P., Stephan, K., Achilleos, N., Bovolo, F., Carter, J., Cavalié, T., Cimò, G., D’Aversa, E., Gwinner, K., Hartogh, P., Huybrighs, H., Langevin, Y., Lellouch, E., Migliorini, A., Palumbo, P., Piccioni, G., Plaut, J. J., Postberg, F., Poulet, F., Retherford, K., Rezac, L., Roth, L., Solomonidou, A., Tobie, G., Tortora, P., Tubiana, C., Wagner, R., Wirström, E., Wurz, P., Zambon, F., Zannoni, M., Barabash, S., Bruzzone, L., Dougherty, M., Gladstone, R., Gurvits, L. I., Hussmann, H., Iess, L., Wahlund, J.-E., Witasse, O., Vallat, C., and Lorente, R.: Characterization of the surfaces and near-surface atmospheres of Ganymede, Europa and Callisto by JUICE, Space Sci. Rev., 220, https://doi.org/10.1007/s11214-024-01089-8, 2024.
Van Hoolst, T., Tobie, G., Vallat, C., Altobelli, N., Bruzzone, L., Cao, H., Dirkx, D., Genova, A., Hussmann, H., Iess, L., Kimura, J., Khurana, K., Lucchetti, A., Mitri, G., Moore, W., Saur, J., Stark, A., Vorburger, A., Wieczorek, M., Aboudan, A., Bergman, J., Bovolo, F., Breuer, D., Cappuccio, P., Carrer, L., Cecconi, B., Choblet, G., De Marchi, F., Fayolle, M., Fienga, A., Futaana, Y., Hauber, E., Kofman, W., Kumamoto, A., Lainey, V., Molyneux, P., Mousis, O., Plaut, J., Puccio, W., Retherford, K., Roth, L., Seignovert, B., Steinbrügge, G., Thakur, S., Tortora, P., Tosi, F., Zannoni, M., Barabash, S., Dougherty, M., Gladstone, R., Gurvits, L. I., Hartogh, P., Palumbo, P., Poulet, F., Wahlund, J.-E., Grasset, O., and Witasse, O.: Geophysical characterization of the interiors of Ganymede, Callisto and Europa by ESA's Jupiter ICy moons Explorer, Space Sci. Rev., 220, https://doi.org/10.1007/s11214-024-01085-y, 2024.
Velez, M. A., Retherford, K. D., Hue, V., Kammer, J. A., Becker, T. M., Gladstone, G. R., Davis, M. W., Greathouse, T. K., Molyneux, P. M., Brooks, S. M., Raut, U., and Versteeg, M. H.: Catalog of Ultraviolet Bright Stars: Strategies for UV Occultation Measurements, Planetary Illumination Modeling, and Sky Map Analyses Using Hybrid IUE-Kurucz Spectra, Planet. Sci. J., 5, 93, https://doi.org/10.3847/PSJ/ad0e70, 2024.
Woods, T. N., Eparvier, F. G., Bailey, S. M., Chamberlin, P. C., Lean, J., Rottman, G. J., Solomon, S. C., Tobiska, W. K., and Woodraska, D. L.: Solar EUV Experiment (SEE): Mission overview and first results, J. Geophys. Res.-Space Phys., 110, https://doi.org/10.1029/2004JA010765, 2005.
Short summary
We describe observations of the Earth and moon performed by the ultraviolet spectrograph (UVS) on the European Space Agency’s JUICE mission during a lunar-Earth flyby in 2024. JUICE-UVS observed UV sunlight reflected by the moon’s surface, and atmospheric emissions at the Earth. The observations provide the first opportunity to test the UVS response to planetary targets and demonstrate the types of measurements to be performed in the 2030s, when JUICE will explore Jupiter and its icy moons.
We describe observations of the Earth and moon performed by the ultraviolet spectrograph (UVS)...
