| Geyser | 2000-01-31 |
|---|---|
| Grand | 0756 E, 2020 E |
| Great Fountain | 0046 E, 1016 E, 2109 E |
| Values for Old Faithful Area | 2000-01-31 |
|---|---|
| Astronomical Twilight Begin | 06:03 |
| Nautical Twilight Begin | 06:37 |
| Civil Twilight Begin | 07:12 |
| Sunrise | 07:43 |
| Sunset | 17:30 |
| Civil Twilight End | 18:01 |
| Nautical Twilight End | 18:36 |
| Astronomical Twilight End | 19:10 |
| Moon Illumination | 23.36% |