| Geyser | 1931-08-31 |
|---|---|
| Ebony | 1030 |
| Little Whirligig | 0000 |
| Minute | 0000 |
| Pinto | 1930 |
| Steamboat | 0000 |
| Vixen | 0000 |
| Whirligig | 1310 |
| Values for Old Faithful Area | 1931-08-31 |
|---|---|
| Astronomical Twilight Begin | 03:59 |
| Nautical Twilight Begin | 04:37 |
| Civil Twilight Begin | 05:13 |
| Sunrise | 05:43 |
| Sunset | 19:03 |
| Civil Twilight End | 19:33 |
| Nautical Twilight End | 20:09 |
| Astronomical Twilight End | 20:48 |
| Moon Illumination | 91.22% |