| Geyser | 1971-02-20 |
|---|---|
| Grotto | 1107 |
| Grotto Fountain | 1055 |
| Old Faithful | 1019 short, 1225 long, 1337 long, 1440 short, 1610 long |
| Riverside | 1117 |
| Values for Old Faithful Area | 1971-02-20 |
|---|---|
| Astronomical Twilight Begin | 05:38 |
| Nautical Twilight Begin | 06:12 |
| Civil Twilight Begin | 06:46 |
| Sunrise | 07:15 |
| Sunset | 17:58 |
| Civil Twilight End | 18:27 |
| Nautical Twilight End | 19:01 |
| Astronomical Twilight End | 19:35 |
| Moon Illumination | 31.85% |