| Values for Old Faithful Area | 1997-05-21 |
|---|---|
| Astronomical Twilight Begin | 03:37 |
| Nautical Twilight Begin | 04:30 |
| Civil Twilight Begin | 05:14 |
| Sunrise | 05:49 |
| Sunset | 20:50 |
| Civil Twilight End | 21:25 |
| Nautical Twilight End | 22:09 |
| Astronomical Twilight End | 23:02 |
| Moon Illumination | 98.56% |