| Geyser | 1999-04-19 |
|---|---|
| Great Fountain | 0038 E, 1028 E, 2113 E |
| Values for Old Faithful Area | 1999-04-19 |
|---|---|
| Astronomical Twilight Begin | 04:44 |
| Nautical Twilight Begin | 05:24 |
| Civil Twilight Begin | 06:01 |
| Sunrise | 06:32 |
| Sunset | 20:12 |
| Civil Twilight End | 20:42 |
| Nautical Twilight End | 21:20 |
| Astronomical Twilight End | 22:00 |
| Moon Illumination | 13.59% |