| Values for Old Faithful Area | 1973-04-21 |
|---|---|
| Astronomical Twilight Begin | 03:39 |
| Nautical Twilight Begin | 04:20 |
| Civil Twilight Begin | 04:57 |
| Sunrise | 05:28 |
| Sunset | 19:15 |
| Civil Twilight End | 19:46 |
| Nautical Twilight End | 20:23 |
| Astronomical Twilight End | 21:04 |
| Moon Illumination | 87.54% |