| | Thumbnail | | Creator | Date | Title / Author / Date / Location | Price | | | Description |
| 8181 |  | Details | Yalden, James Ernest Grant | 1920 |
| Early 1920 Blueprint Celestial Chart of 589 Bright Stars by J. Ernest G. Yalden |
|
Yalden, James Ernest Grant |
|
| 1920 |
| LOC: |
| $400.00 | Yalden--James-Ernest-Grant | Early-1920-Blueprint-Celestial-Chart-of-589-Bright-Stars-by-J--Ernest-G--Yalden | Blueprint celestial chart compiled by J. Ernest G. Yalden in 1920, plotting 589 bright stars, including 21 variable stars, across the sky north of declination -30 degrees. Pale lettering and star symbols stand against a dark blue ground, with the heavens arranged in a circular projection centered on the north celestial pole.<br><br>
The chart extends beyond the northern celestial hemisphere to include stars as far as 30 degrees south of the celestial equator. Constellations are named without pictorial figures, emphasizing the positions and brightness of individual stars. Concentric declination circles and radial lines of right ascension provide the coordinate framework, with Roman numerals marking hours around the circumference. Tables in the corners give the sidereal time of mean noon for dates throughout the year.<br><br>
Yalden credits volumes XLVIII, No. IV, and LV of the Annals of Harvard College Observatory as his sources, recording photometric magnitudes to the nearest tenth. The date 1920 appears beneath his name; "Epoch 1900" identifies the reference date for the stellar coordinates. The chart brings Harvard's observational data into a compact visual reference for locating bright stars and comparing their apparent brightness.<br><br> |