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 High level (H2) calcium vapour surrounding the Great Sun-spot of 1903 1903
Medium level (H) calcium vapour, surrounding the great sun-spot of 1903, October 10, 9h. 39m. C.S.T. slit at 3966.5, suns diam = .77 metre, taken with the Rumford spectroheliograph and 40-inch refractor of the Yerkes Observatory by G.E. Hale and F. Ellerman Medium level (H) calcium vapour 1903
Higher (H1) calcium vapour surrounding the great sun-spot of 1903, October 10, 10h, 59m. C.S. T., slit at 3967.5 suns diam. = .77 metre taken with the Rumford spectoheliograph and 40-inch refractor of the Yerkes Observatory by G.E. Hale and F. Ellerman Higher (H1) calcium vapour surrounding the great sun-spot of 1903 1903
One of of three platinotype prints of engravings in, 'Selenographia' by Johannes Hevelius, 1647 showing sunspots observed through a telescope. From page 500 and dated 28 October to 6 November 1642 Drawing of sunspots, German, 28 October 1642. 1647
One of of three platinotype prints of engravings in, 'Selenographia' by Johannes Hevelius, 1647 showing sunspots observed through a telescope. From page 519 and dated 3 May to 16 May 1644. Drawing of sunspots, German, 28 October 1642. 1647
One of of three platinotype prints of engravings in, 'Selenographia' by Johannes Hevelius, 1647 showing sunspots observed through a telescope. From page 525 and dated 27 August to 8 October 1644. Drawing of sunspots, German, 28 October 1642. 1647
Sun's disc in "K" light, 1903, July 8, 11.4 am, exposure, 53 secs enlarged 3 diam, taken with the spectroheliograph at the Solar Physics Observatory, South Kensington Sun's disc in "K" light 1903
Calcium and Hydrogen Flocculi, surrounding the great Sun-spot of 1903, October 9 low level H1. slit at 3962, 3h 43m. C.S.T., medium level H1. slit at 3966, 3h 43m. C.S.T. taken with the Rumford Spectroheliograph and 40-inch refractor of Yerkes Observatory by G.E. Hale and F. Ellerman Calcium and Hydrogen Flocculi 1903
Calcium and hydrogen flocculi, surrounding the great sun-spot of 1903, October 9, High level H2 slit at 3968.6, 3h.30m. C.S.T. Hydrogen slit at centre of Hs, 1h. 4m C.S.T., taken with the Rumford Spectroheliograph and 40-inch refractor at Yerkes Observatory by G.E. Hale and F. Ellerman Calcium and hydrogen flocculi 1903
One of three photographs in passe partout frame [X13] showing the Sun with spots in white light on May 16, 1951. One of three photographs in passe partout frame X13 showing the Sun with spots in white light on May 16 1951
One of three photographs in passe partout frame [X13] showing the Sun with spots in white light on May 18, 1951. One of three photographs in passe partout frame X13 showing the Sun with spots in white light on May 18 1951
One of three photographs in passe partout frame [X13] showing the Sun with spots in white light on May 13, 1951. One of three photographs in passe partout frame X13 showing the Sun with spots in white light on May 13 1951
Collection of three platinotype prints of engravings in, 'Selenographia' by Johannes Hevelius, 1647 showing sunspots observed through a telescope. Collection of three platinotype prints of engravings in 1647