| Values for Old Faithful Area | 1991-09-21 |
|---|---|
| Astronomical Twilight Begin | 05:30 |
| Nautical Twilight Begin | 06:05 |
| Civil Twilight Begin | 06:40 |
| Sunrise | 07:09 |
| Sunset | 19:23 |
| Civil Twilight End | 19:52 |
| Nautical Twilight End | 20:26 |
| Astronomical Twilight End | 21:01 |
| Moon Illumination | 92.62% |