| Geyser | 1976-10-21 |
|---|---|
| Castle | 0800 ie, 1650 ie |
| Grand | 1335 |
| Great Fountain | 1025, 1845 |
| Old Faithful | 0734 ie, 0846 long, 0954 long, 1104 long, 1219 long, 1338 long, 1510 long, 1614 short, 1720 long |
| Riverside | 1205 |
| Values for Old Faithful Area | 1976-10-21 |
|---|---|
| Astronomical Twilight Begin | 06:09 |
| Nautical Twilight Begin | 06:43 |
| Civil Twilight Begin | 07:17 |
| Sunrise | 07:46 |
| Sunset | 18:29 |
| Civil Twilight End | 18:58 |
| Nautical Twilight End | 19:32 |
| Astronomical Twilight End | 20:06 |
| Moon Illumination | 5.76% |