| Name | Date/time | RA | Dec | Magnitude | Filter | Site Code |
|---|---|---|---|---|---|---|
| C/1989 Y1 | 1990 03 16.77610 | 00 42 11.86 | +42 14 56.9 | 046 | ||
| C/1989 Y1 | 1990 03 16.77853 | 00 42 12.65 | +42 14 57.1 | 046 | ||
| C/1989 Y1 | 1990 03 17.78646 | 00 47 03.64 | +42 19 17.7 | 046 | ||
| C/1989 Y1 | 1990 03 17.78924 | 00 47 04.60 | +42 19 17.2 | 046 | ||
| C/1989 Y1 | 1990 03 19.40758 | 00 54 54.04 | +42 25 08.8 | 897 | ||
| C/1989 Y1 | 1990 03 19.41134 | 00 54 54.72 | +42 25 07.7 | 897 | ||
| C/1989 Y1 | 1990 03 19.41447 | 00 54 55.56 | +42 25 06.6 | 897 | ||
| C/1989 Y1 | 1990 03 27.17299 | 01 32 34.95 | +42 33 23.1 | 657 | ||
| C/1989 Y1 | 1990 03 27.20111 | 01 32 43.45 | +42 33 24.5 | 657 | ||
| C/1989 Y1 | 1990 03 28.18618 | 01 37 29.30 | +42 32 05.8 | 657 | ||
| C/1989 Y1 | 1990 03 28.19174 | 01 37 30.82 | +42 32 05.7 | 657 | ||
| C/1989 Y1 | 1990 03 31.81319 | 01 54 56.92 | +42 22 51.9 | 026 | ||
| C/1989 Y1 | 1990 04 04.20660 | 02 11 05.23 | +42 07 48.8 | 657 | ||
| C/1989 Y1 | 1990 04 05.18375 | 02 15 41.46 | +42 02 23.5 | 657 | ||
| C/1989 Y1 | 1990 04 05.19347 | 02 15 44.12 | +42 02 19.7 | 657 | ||
| C/1989 Y1 | 1990 04 27.84549 | 03 53 20.11 | +38 00 56.9 | 587 | ||
| C/1989 Y1 | 1990 05 15.46632 | 04 55 02.56 | +33 13 16.2 | 15.0 | T | 372 |
| C/1989 Y1 | 1990 05 15.47014 | 04 55 03.24 | +33 13 10.1 | 372 | ||
| C/1989 Y1 | 1990 10 16.75720 | 09 10 32.09 | -16 51 20.5 | 15.0 | T | 413 |
| C/1989 Y1 | 1990 10 17.75832 | 09 11 07.91 | -17 12 19.2 | 413 |