| Values for Old Faithful Area | 1997-04-20 |
|---|---|
| Astronomical Twilight Begin | 04:41 |
| Nautical Twilight Begin | 05:21 |
| Civil Twilight Begin | 05:59 |
| Sunrise | 06:30 |
| Sunset | 20:14 |
| Civil Twilight End | 20:44 |
| Nautical Twilight End | 21:22 |
| Astronomical Twilight End | 22:03 |
| Moon Illumination | 93.49% |