| Geyser | 1981-07-15 |
|---|---|
| Echinus | 0942, 1037 |
| Values for Old Faithful Area | 1981-07-15 |
|---|---|
| Astronomical Twilight Begin | 03:36 |
| Nautical Twilight Begin | 04:32 |
| Civil Twilight Begin | 05:17 |
| Sunrise | 05:53 |
| Sunset | 21:05 |
| Civil Twilight End | 21:40 |
| Nautical Twilight End | 22:26 |
| Astronomical Twilight End | 23:22 |
| Moon Illumination | 96.2% |