| Geyser | 1999-05-17 |
|---|---|
| Great Fountain | 0108 E, 0858 E, 1943 E |
| Values for Old Faithful Area | 1999-05-17 |
|---|---|
| Astronomical Twilight Begin | 03:45 |
| Nautical Twilight Begin | 04:36 |
| Civil Twilight Begin | 05:19 |
| Sunrise | 05:53 |
| Sunset | 20:45 |
| Civil Twilight End | 21:19 |
| Nautical Twilight End | 22:02 |
| Astronomical Twilight End | 22:53 |
| Moon Illumination | 4.63% |