| Values for Old Faithful Area | 1977-09-20 |
|---|---|
| Astronomical Twilight Begin | 05:30 |
| Nautical Twilight Begin | 06:05 |
| Civil Twilight Begin | 06:39 |
| Sunrise | 07:08 |
| Sunset | 19:24 |
| Civil Twilight End | 19:53 |
| Nautical Twilight End | 20:28 |
| Astronomical Twilight End | 21:03 |
| Moon Illumination | 49.92% |