| Geyser | 1977-04-28 |
|---|---|
| Beehive | 1635 |
| Grand | 1007 |
| Lion | 1635 |
| Old Faithful | 0932, 1045 long, 1200 long, 1314 long, 1420 long, 1529 long, 1640 |
| Pink Cone | 0850 |
| Values for Old Faithful Area | 1977-04-28 |
|---|---|
| Astronomical Twilight Begin | 04:24 |
| Nautical Twilight Begin | 05:07 |
| Civil Twilight Begin | 05:46 |
| Sunrise | 06:17 |
| Sunset | 20:23 |
| Civil Twilight End | 20:55 |
| Nautical Twilight End | 21:34 |
| Astronomical Twilight End | 22:17 |
| Moon Illumination | 66.58% |