| Geyser | 1991-10-27 |
|---|---|
| Fantail | 1991-10-20 0000-1992-05-01 2359 |
| Values for Old Faithful Area | 1991-10-27 |
|---|---|
| Astronomical Twilight Begin | 05:16 |
| Nautical Twilight Begin | 05:49 |
| Civil Twilight Begin | 06:23 |
| Sunrise | 06:53 |
| Sunset | 17:20 |
| Civil Twilight End | 17:50 |
| Nautical Twilight End | 18:24 |
| Astronomical Twilight End | 18:58 |
| Moon Illumination | 82.38% |