| Values for Old Faithful Area | 1973-07-21 |
|---|---|
| Astronomical Twilight Begin | 03:46 |
| Nautical Twilight Begin | 04:39 |
| Civil Twilight Begin | 05:24 |
| Sunrise | 05:58 |
| Sunset | 21:00 |
| Civil Twilight End | 21:35 |
| Nautical Twilight End | 22:19 |
| Astronomical Twilight End | 23:12 |
| Moon Illumination | 70.2% |