1928 QC. Discovered 1928 Aug. 15 by P. F. Shajn at Simeis. Independently discovered 1928 Aug. 24 by M. F. Wolf at Heidelberg.

Named in honor of the laboratory assistant and calculator Katja (Ekaterina) Ios’ko of the discovery observatory. She was the daughter of the Simeis mechanician Iosif Gavrilovich Ios’ko. (N. S. Samojlova-Yakhontova; N. Solovaya; N. S. Chernykh; V. A. Shor)