| Geyser | 1999-12-04 |
|---|---|
| Grand | 1141 E, 2205 E |
| Great Fountain | 0645 E, 1611 E |
| Values for Old Faithful Area | 1999-12-04 |
|---|---|
| Astronomical Twilight Begin | 05:58 |
| Nautical Twilight Begin | 06:33 |
| Civil Twilight Begin | 07:09 |
| Sunrise | 07:42 |
| Sunset | 16:44 |
| Civil Twilight End | 17:17 |
| Nautical Twilight End | 17:53 |
| Astronomical Twilight End | 18:28 |
| Moon Illumination | 11.73% |