| Geyser | 1999-10-27 |
|---|---|
| Grand | 0708 E, 1953 E |
| Great Fountain | 0027 E, 1120 E, 2014 E |
| Values for Old Faithful Area | 1999-10-27 |
|---|---|
| Astronomical Twilight Begin | 06:16 |
| Nautical Twilight Begin | 06:49 |
| Civil Twilight Begin | 07:24 |
| Sunrise | 07:53 |
| Sunset | 18:20 |
| Civil Twilight End | 18:50 |
| Nautical Twilight End | 19:24 |
| Astronomical Twilight End | 19:58 |
| Moon Illumination | 91.95% |