Wunda has a prominent albedo feature on its floor, which takes the shape of a ring of bright material at least 10 km in radial width. The reason for its brightness, which stands out from the very dark composition of the moon as a whole, is unknown. It may be either a fresh impact deposit or a deposit of carbon dioxide ice, which formed when the radiolytically formed carbon dioxide migrated from all over the surface of Umbriel and got trapped inside relatively cold Wunda.
^Sori, Michael M.; Bapst, Jonathan; Bramson, Ali M.; Byrne, Shane; Landis, Margaret E. (2017-07-01). "A Wunda-full world? Carbon dioxide ice deposits on Umbriel and other Uranian moons". Icarus. 290: 1–13. Bibcode:2017Icar..290....1S. doi:10.1016/j.icarus.2017.02.029.
Plescia, J. B. (December 30, 1987). "Cratering history of the Uranian satellites: Umbriel, Titania and Oberon". Journal of Geophysical Research. 92 (A13): 14, 918–14, 932. Bibcode:1987JGR....9214918P. doi:10.1029/JA092iA13p14918. ISSN 0148-0227.
Smith, B. A.; Soderblom, L. A.; Beebe, A.; Bliss, D.; Boyce, J. M.; Brahic, A.; Briggs, G. A.; Brown, R. H.; Collins, S. A. (4 July 1986). "Voyager 2 in the Uranian System: Imaging Science Results". Science. 233 (4759): 43–64. Bibcode:1986Sci...233...43S. doi:10.1126/science.233.4759.43. PMID17812889.
USGS/IAU (October 1, 2006). "Wunda on Umbriel". Gazetteer of Planetary Nomenclature. USGS Astrogeology. Retrieved 2012-02-22.