Extending the NIR auroral map of Uranus through the 21st century

Over 30 years of near infrared (NIR) observations at Uranus starting in 1992 with Trafton, et al., 1993, it is only in the last 5 years we have had any significant breakthroughs in mapping of NIR auroral morphology. The first confirmed auroral observations by Thomas, et al., (in review) and a tentative auroral detection by Melin, et al., (2019) have now shown that NIR aurora detections at Uranus are possible from ground-based observations. Thomas, et al. concluded that sections of the NIR northern aurora were observed for the first time and even outlined the first NIR auroral arcs, however due to observational limitations and the loss of Uranian Longitude System (ULS) a complete map could not be accomplished. With the ULS southern hemisphere now predominately facing the Earth (since the planet’s equinox of 2007), we are poised to reveal the auroral morphology of the southern aurora with detail never seen before. Success in this aim will yield the first insights into ionospheric magnetospheric interactions at Uranus when exposed to dynamic changes in the planet's magnetic field orientation to the solar wind and the first NIR maps to guide auroral expectations at sub-Neptune exoplanets.

In this study, we have taken ground-based observations of H₃⁺ emissions from Uranus’s Equinox to 2022 and construct the first NIR composite map of the geographical equator and southern hemisphere to identify if similar auroral features appear as was observed in 2006, and to extend the NIR auroral mapping across Uranus.