| Geyser | 1991-05-27 |
|---|---|
| Echinus | 1127 |
| Pearl | 1200 |
| Values for Old Faithful Area | 1991-05-27 |
|---|---|
| Astronomical Twilight Begin | 03:28 |
| Nautical Twilight Begin | 04:24 |
| Civil Twilight Begin | 05:09 |
| Sunrise | 05:44 |
| Sunset | 20:55 |
| Civil Twilight End | 21:31 |
| Nautical Twilight End | 22:16 |
| Astronomical Twilight End | 23:12 |
| Moon Illumination | 98.55% |