| Geyser | 1987-08-30 |
|---|---|
| Blue Mud Steam Vent | 1200 |
| Pearl | 1200 |
| Porkchop | 1200 |
| Second Erupter | 1200 |
| Values for Old Faithful Area | 1987-08-30 |
|---|---|
| Astronomical Twilight Begin | 04:58 |
| Nautical Twilight Begin | 05:36 |
| Civil Twilight Begin | 06:13 |
| Sunrise | 06:43 |
| Sunset | 20:04 |
| Civil Twilight End | 20:34 |
| Nautical Twilight End | 21:10 |
| Astronomical Twilight End | 21:49 |
| Moon Illumination | 29.98% |