| Geyser | 1999-01-30 |
|---|---|
| Great Fountain | 0518 E, 1523 E |
| Values for Old Faithful Area | 1999-01-30 |
|---|---|
| Astronomical Twilight Begin | 06:03 |
| Nautical Twilight Begin | 06:37 |
| Civil Twilight Begin | 07:12 |
| Sunrise | 07:43 |
| Sunset | 17:29 |
| Civil Twilight End | 18:00 |
| Nautical Twilight End | 18:35 |
| Astronomical Twilight End | 19:09 |
| Moon Illumination | 97.64% |