| Geyser | 1991-05-16 |
|---|---|
| Blue Mud Steam Vent | 1200 |
| Branch Spring | 1200 |
| Echinus | 1448 |
| Whistle | 1991-05-12 0000-1991-05-24 0000 |
| Values for Old Faithful Area | 1991-05-16 |
|---|---|
| Astronomical Twilight Begin | 03:47 |
| Nautical Twilight Begin | 04:37 |
| Civil Twilight Begin | 05:20 |
| Sunrise | 05:54 |
| Sunset | 20:44 |
| Civil Twilight End | 21:18 |
| Nautical Twilight End | 22:01 |
| Astronomical Twilight End | 22:51 |
| Moon Illumination | 6.15% |