| Geyser | 1999-04-11 |
|---|---|
| Great Fountain | 0033 E, 1028 E, 2228 E |
| Values for Old Faithful Area | 1999-04-11 |
|---|---|
| Astronomical Twilight Begin | 05:02 |
| Nautical Twilight Begin | 05:40 |
| Civil Twilight Begin | 06:16 |
| Sunrise | 06:46 |
| Sunset | 20:02 |
| Civil Twilight End | 20:32 |
| Nautical Twilight End | 21:08 |
| Astronomical Twilight End | 21:46 |
| Moon Illumination | 28.98% |