Free Access
| Date | UT | JD | exp. | Range |
| 1991 | s | Å | ||
| March 31 | 3:42 | 8 346.66 | 300 | 3870-5000 |
| April 2 | 2:20 | 8 348.60 | 120 | 5980-7130 |
| April 2 | 2:28 | 8 348.60 | 300 | " |
| April 2 | 3:22 | 8 348.64 | 300 | 4920-6060 |
| April 2 | 3:51 | 8 348.66 | 600 | 3900-5040 |
| July 2 | 0:29 | 84 39.52 | 2400 | 3960-5100 |
Notes. JD: Julian date - 2 440 000. UT: Universal time at start of exposure.
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