| Values for Old Faithful Area | 1991-07-15 |
|---|---|
| Astronomical Twilight Begin | 03:35 |
| Nautical Twilight Begin | 04:31 |
| Civil Twilight Begin | 05:17 |
| Sunrise | 05:52 |
| Sunset | 21:05 |
| Civil Twilight End | 21:41 |
| Nautical Twilight End | 22:26 |
| Astronomical Twilight End | 23:23 |
| Moon Illumination | 16.54% |