| Geyser | 1999-02-25 |
|---|---|
| Great Fountain | 0713 E, 1938 E |
| Twin | 1400 A |
| Values for Old Faithful Area | 1999-02-25 |
|---|---|
| Astronomical Twilight Begin | 05:30 |
| Nautical Twilight Begin | 06:04 |
| Civil Twilight Begin | 06:38 |
| Sunrise | 07:07 |
| Sunset | 18:05 |
| Civil Twilight End | 18:34 |
| Nautical Twilight End | 19:08 |
| Astronomical Twilight End | 19:42 |
| Moon Illumination | 73.6% |