TURNER, RALPH. B.1935.
4 large calligraphic sketches of Phobos's northern and southern hemispheres, probably Sheridan, OR, 1976, 2 being contour diagrams, and 2 being shaded contour diagrams, ink and white gouache, each on 2 joined sheets of acetate, overall 1000 x 1500 mm to 1060 x 1440 mm, signed "R. Turner, 1976," framed.
Phobos is the larger and closer of the two natural satellites of Mars, and was discovered in 1877. Turner has a degree in calligraphy from Reed College in Oregon.