| Geyser | 1966-08-31 |
|---|---|
| Cistern Spring | 0800 |
| Colloidal Pool | 1200 |
| Echinus | 0916, 1014, 1107, 1206, 1303, 1457, 1558, 1657 |
| Event Non-Geyser Related | 0000 |
| Ledge | 0700 A |
| Steamboat | 0800-1645 |
| Values for Old Faithful Area | 1966-08-31 |
|---|---|
| Astronomical Twilight Begin | 05:00 |
| Nautical Twilight Begin | 05:38 |
| Civil Twilight Begin | 06:14 |
| Sunrise | 06:44 |
| Sunset | 20:02 |
| Civil Twilight End | 20:32 |
| Nautical Twilight End | 21:08 |
| Astronomical Twilight End | 21:47 |
| Moon Illumination | 99.95% |