Two ALSs, one signed “Clyde W. Tombaugh,” the other signed “Clyde W. Tombaugh, Emeritus Professor of Astronomy,” both one page, New Mexico State University letterhead, dated 1984 and 1985 respectively. One reads, in part: “As to the question of possible more planets, there might be more which were too faint to be recorded on the photographic plates I took with the 13–inch telescope. To explore only 2 magnitudes fainter would increase the work over ten-fold because of the much greater number of star images.” In fine condition, with intersecting folds to one letter, and light wrinkling to the other. RRAuction COA.
