| Geyser | 1999-02-23 |
|---|---|
| Great Fountain | 0233 E, 1458 E |
| Values for Old Faithful Area | 1999-02-23 |
|---|---|
| Astronomical Twilight Begin | 05:33 |
| Nautical Twilight Begin | 06:07 |
| Civil Twilight Begin | 06:41 |
| Sunrise | 07:10 |
| Sunset | 18:02 |
| Civil Twilight End | 18:32 |
| Nautical Twilight End | 19:05 |
| Astronomical Twilight End | 19:39 |
| Moon Illumination | 51.99% |