Asteroids discovered on May 21
27 named asteroids.
| # | Asteroid | Discovered | Discoverer |
|---|---|---|---|
| 1 | (197) Arete | 1879-05-21 | J. Palisa |
| 2 | (480) Hansa | 1901-05-21 | Wolf, M. F., Carnera, L. |
| 3 | (872) Holda | 1917-05-21 | M. F. Wolf |
| 4 | (873) Mechthild | 1917-05-21 | M. F. Wolf |
| 5 | (982) Franklina | 1922-05-21 | H. E. Wood |
| 6 | (1304) Arosa | 1928-05-21 | K. Reinmuth |
| 7 | (1196) Sheba | 1931-05-21 | C. Jackson |
| 8 | (2731) Cucula | 1982-05-21 | P. Wild |
| 9 | (3018) Godiva | 1982-05-21 | E. Bowell |
| 10 | (3305) Ceadams | 1985-05-21 | Gilmore, A. C., Kilmartin, P. M. |
| 11 | (6041) Juterkilian | 1990-05-21 | E. F. Helin |
| 12 | (6192) Javiergorosabel | 1990-05-21 | E. F. Helin |
| 13 | (6310) Jankonke | 1990-05-21 | E. F. Helin |
| 14 | (6713) Coggie | 1990-05-21 | E. F. Helin |
| 15 | (7758) Poulanderson | 1990-05-21 | E. F. Helin |
| 16 | (9945) Karinaxavier | 1990-05-21 | E. F. Helin |
| 17 | (7433) Pellegrini | 1993-05-21 | Farra d'Isonzo |
| 18 | (48619) Jianli | 1995-05-21 | Beijing Schmidt CCD Asteroid Program |
| 19 | (14072) Volterra | 1996-05-21 | P. G. Comba |
| 20 | (14960) Yule | 1996-05-21 | P. G. Comba |
| 21 | (13239) Kana | 1998-05-21 | A. Nakamura |
| 22 | (27613) Annalou | 2001-05-21 | LINEAR |
| 23 | (46280) Hollar | 2001-05-21 | Pravec, P., Kusnirak, P. |
| 24 | (108496) Sullenberger | 2001-05-21 | R. A. Tucker |
| 25 | (456627) Cristianmartins | 2007-05-21 | Astronomical Research Observatory |
| 26 | (251633) Kivelson | 2010-05-21 | WISE |
| 27 | (454419) Hansklausreif | 2010-05-21 | WISE |