| Geyser | 1987-09-01 |
|---|---|
| Blue | 1200 |
| Dark Cavern | 1200 |
| Values for Old Faithful Area | 1987-09-01 |
|---|---|
| Astronomical Twilight Begin | 05:01 |
| Nautical Twilight Begin | 05:39 |
| Civil Twilight Begin | 06:15 |
| Sunrise | 06:45 |
| Sunset | 20:00 |
| Civil Twilight End | 20:30 |
| Nautical Twilight End | 21:06 |
| Astronomical Twilight End | 21:45 |
| Moon Illumination | 51.13% |