| S/2019 S 21 | |
| Discovery Ref: |   |
| Discoverer: | Scott S. Sheppard, David C. Jewitt, Jan Kleyna, Brett J. Gladman, E. Ashton |
| Discovered: | 2019 |
| Orbit Ref: |   |
| Eccentricity: | 0.155 |
| Period: | -4.480 yrs (1,636.32 d) |
| Inclination: | 171.9° |
| Satellite Of: | Saturn |
| Group: | Norse group |
| Abs Magnitude: | 16.2 |
S/2019 S 21 is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, Edward Ashton, Brett J. Gladman, Jean-Marc Petit and Mike Alexandersen on May 16, 2023 from observations taken between February 2, 2006 and July 8, 2021. S/2019 S 21 is about 4 kilometers in diameter, and orbits Saturn at an average distance of 26.076 Gm in 1,572.06 days, at an inclination of 171.5, orbits in retrograde direction and eccentricity of 0.125. S/2019 S 21 belongs to the Norse group and one of the most distant moons from Saturn along with S/2004 S 26, S/2004 S 52 and S/2020 S 9.