| Geyser | 1999-12-06 |
|---|---|
| Grand | 0802 E, 1941 E |
| Great Fountain | 0707 E, 1621 E |
| Values for Old Faithful Area | 1999-12-06 |
|---|---|
| Astronomical Twilight Begin | 06:00 |
| Nautical Twilight Begin | 06:35 |
| Civil Twilight Begin | 07:11 |
| Sunrise | 07:44 |
| Sunset | 16:43 |
| Civil Twilight End | 17:16 |
| Nautical Twilight End | 17:53 |
| Astronomical Twilight End | 18:28 |
| Moon Illumination | 2.46% |