High level (H2) calcium vapour surrounding the Great Sun-spot of 1903
- Made:
- 1903 in Williams Bay
- photographer:
- F Ellerman and George Ellery Hale
High level (H2) calcium vapour surrounding the Great Sun-spot of 1903, October 10, 9h. 9m. C. S.T. slit at 3968.6 Sun's diam. = .77 metre, taken with the Rumford spectroheliograph and 40-inch refractor of the Yerkes Observatory by G.E. Hale and F. Ellerman