| Geyser | 1981-06-21 |
|---|---|
| Echinus | 1044 |
| Steamvalve Spring | 1220 |
| Sunday | 1432, 1501, 1507 |
| Whirligig | 1400, 1500 |
| Values for Old Faithful Area | 1981-06-21 |
|---|---|
| Astronomical Twilight Begin | 03:09 |
| Nautical Twilight Begin | 04:13 |
| Civil Twilight Begin | 05:01 |
| Sunrise | 05:38 |
| Sunset | 21:11 |
| Civil Twilight End | 21:48 |
| Nautical Twilight End | 22:37 |
| Astronomical Twilight End | 23:40 |
| Moon Illumination | 87.41% |