| Geyser | 1991-10-25 |
|---|---|
| Fantail | 1991-10-20 0000-1992-05-01 2359 |
| Values for Old Faithful Area | 1991-10-25 |
|---|---|
| Astronomical Twilight Begin | 06:13 |
| Nautical Twilight Begin | 06:47 |
| Civil Twilight Begin | 07:21 |
| Sunrise | 07:51 |
| Sunset | 18:23 |
| Civil Twilight End | 18:53 |
| Nautical Twilight End | 19:27 |
| Astronomical Twilight End | 20:01 |
| Moon Illumination | 96.01% |