| Geyser | 1991-07-31 |
|---|---|
| Constant | 1532 |
| Echinus | 0800 ie maj, 1118, 1355, 1445, 1545, 1640 |
| Emerald Spring | 1200 |
| Whirligig | 0934 |
| Values for Old Faithful Area | 1991-07-31 |
|---|---|
| Astronomical Twilight Begin | 04:04 |
| Nautical Twilight Begin | 04:53 |
| Civil Twilight Begin | 05:35 |
| Sunrise | 06:08 |
| Sunset | 20:50 |
| Civil Twilight End | 21:23 |
| Nautical Twilight End | 22:05 |
| Astronomical Twilight End | 22:54 |
| Moon Illumination | 81.62% |