| Values for Old Faithful Area | 1977-04-23 |
|---|---|
| Astronomical Twilight Begin | 03:34 |
| Nautical Twilight Begin | 04:16 |
| Civil Twilight Begin | 04:54 |
| Sunrise | 05:25 |
| Sunset | 19:17 |
| Civil Twilight End | 19:48 |
| Nautical Twilight End | 20:26 |
| Astronomical Twilight End | 21:08 |
| Moon Illumination | 19.92% |