| 3.6 km || |-id=650 bgcolor=#E9E9E9 | 20650 || || — || October 10, 1999 || Socorro || LINEAR || — || align=right | 4.5 km || |-id=651 bgcolor=#E9E9E9 | 20651 || || — || October 1, 1999 || Catalina || CSS || — || align=right | 5.9 km || |-id=652 bgcolor=#fefefe | 20652 || || — || October 2, 1999 || Catalina || CSS || — || align=right | 5.6 km || |-id=653 bgcolor=#d6d6d6 | 20653 || || — || October 7, 1999 || Catalina || CSS || — || align=right | 18 km || |-id=654 bgcolor=#d6d6d6 | 20654 || || — || October 8, 1999 || Catalina || CSS || — || align=right | 11 km || |-id=655 bgcolor=#d6d6d6 | 20655 || || — || October 8, 1999 || Catalina || CSS || — || align=right | 11 km || |-id=656 bgcolor=#d6d6d6 | 20656 || || — || October 9, 1999 || Socorro || LINEAR || THM || align=right | 7.9 km || |-id=657 bgcolor=#d6d6d6 | 20657 Alvarez-Candal || || || October 14, 1999 || Anderson Mesa || LONEOS || — || align=right | 10 km || |-id=658 bgcolor=#fefefe | 20658 Bushmarinov || || || October 3, 1999 || Socorro || LINEAR || V || align=right | 2.4 km || |-id=659 bgcolor=#d6d6d6 | 20659 || 1999 UE || — || October 16, 1999 || Višnjan Observatory || K. Korlević || THM || align=right | 8.1 km || |-id=660 bgcolor=#d6d6d6 | 20660 || 1999 UF || — || October 16, 1999 || Višnjan Observatory || K. Korlević || HYG || align=right | 11 km || |-id=661 bgcolor=#d6d6d6 | 20661 || 1999 UZ || — || October 16, 1999 || Višnjan Observatory || K. Korlević || THM || align=right | 8.0 km || |-id=662 bgcolor=#E9E9E9 | 20662 || || — || October 16, 1999 || Višnjan Observatory || K. Korlević || — || align=right | 5.5 km || |-id=663 bgcolor=#fefefe | 20663 || || — || October 19, 1999 || Fountain Hills || C. W. Juels || V || align=right | 3.0 km || |-id=664 bgcolor=#d6d6d6 | 20664 Senec || || || October 31, 1999 || Modra || A. Galád, J. Tóth || SYL7:4 || align=right | 15 km || |-id=665 bgcolor=#d6d6d6 | 20665 || || — || October 29, 1999 || Catalina || CSS || — || align=right | 11 km || |-id=666 bgcolor=#d6d6d6 | 20666 || || —