| Geyser | 1999-05-20 |
|---|---|
| Great Fountain | 0708 E, 1613 E |
| Values for Old Faithful Area | 1999-05-20 |
|---|---|
| Astronomical Twilight Begin | 03:40 |
| Nautical Twilight Begin | 04:32 |
| Civil Twilight Begin | 05:16 |
| Sunrise | 05:50 |
| Sunset | 20:49 |
| Civil Twilight End | 21:23 |
| Nautical Twilight End | 22:07 |
| Astronomical Twilight End | 22:59 |
| Moon Illumination | 29.2% |