| Geyser | 1999-12-08 |
|---|---|
| Grand | 1317 E, 2347 E |
| Great Fountain | 0102 E, 1032 E, 2011 E |
| Values for Old Faithful Area | 1999-12-08 |
|---|---|
| Astronomical Twilight Begin | 06:01 |
| Nautical Twilight Begin | 06:37 |
| Civil Twilight Begin | 07:13 |
| Sunrise | 07:46 |
| Sunset | 16:43 |
| Civil Twilight End | 17:16 |
| Nautical Twilight End | 17:53 |
| Astronomical Twilight End | 18:28 |
| Moon Illumination | 0.1% |