| Geyser | 1973-09-20 |
|---|---|
| Blue | 1100 |
| Congress Pool | 1800 |
| Echinus | 1010 A, 1155, 1248, 1437, 1531, 1626 |
| Ledge | 1800 |
| Little Whirligig | 1100, 1804 |
| Orby | 0930 |
| Whirligig | 1800, 1800 |
| Values for Old Faithful Area | 1973-09-20 |
|---|---|
| Astronomical Twilight Begin | 05:29 |
| Nautical Twilight Begin | 06:05 |
| Civil Twilight Begin | 06:39 |
| Sunrise | 07:08 |
| Sunset | 19:25 |
| Civil Twilight End | 19:53 |
| Nautical Twilight End | 20:28 |
| Astronomical Twilight End | 21:03 |
| Moon Illumination | 43.5% |