| Geyser | 1987-08-22 |
|---|---|
| Bear Den | 1200 |
| Values for Old Faithful Area | 1987-08-22 |
|---|---|
| Astronomical Twilight Begin | 04:45 |
| Nautical Twilight Begin | 05:25 |
| Civil Twilight Begin | 06:03 |
| Sunrise | 06:34 |
| Sunset | 20:18 |
| Civil Twilight End | 20:49 |
| Nautical Twilight End | 21:26 |
| Astronomical Twilight End | 22:07 |
| Moon Illumination | 4.63% |