| Geyser | 1999-10-28 |
|---|---|
| Grand | 0711 E, 1720 E |
| Great Fountain | 0506 E, 1347 E |
| Values for Old Faithful Area | 1999-10-28 |
|---|---|
| Astronomical Twilight Begin | 06:17 |
| Nautical Twilight Begin | 06:51 |
| Civil Twilight Begin | 07:25 |
| Sunrise | 07:55 |
| Sunset | 18:19 |
| Civil Twilight End | 18:48 |
| Nautical Twilight End | 19:23 |
| Astronomical Twilight End | 19:56 |
| Moon Illumination | 84.25% |