| Geyser | 1999-11-21 |
|---|---|
| Grand | 0117 E, 1114 E, 2302 E |
| Great Fountain | 0242 E, 1312 E |
| Values for Old Faithful Area | 1999-11-21 |
|---|---|
| Astronomical Twilight Begin | 05:45 |
| Nautical Twilight Begin | 06:19 |
| Civil Twilight Begin | 06:55 |
| Sunrise | 07:27 |
| Sunset | 16:51 |
| Civil Twilight End | 17:22 |
| Nautical Twilight End | 17:58 |
| Astronomical Twilight End | 18:33 |
| Moon Illumination | 94.07% |