| Geyser | 1999-04-08 |
|---|---|
| Great Fountain | 0033 E, 1313 E, 2238 E |
| Values for Old Faithful Area | 1999-04-08 |
|---|---|
| Astronomical Twilight Begin | 05:08 |
| Nautical Twilight Begin | 05:46 |
| Civil Twilight Begin | 06:21 |
| Sunrise | 06:51 |
| Sunset | 19:58 |
| Civil Twilight End | 20:28 |
| Nautical Twilight End | 21:04 |
| Astronomical Twilight End | 21:41 |
| Moon Illumination | 58.5% |