Lot of six FDCs, each signed in ink by Clyde W. Tombaugh (discover of Pluto) and J.W. Christy (discover of Pluto’s satellite). The FDCs bear cachets honoring Pioneer Jupiter, Mariner, United States Space Program, Probing the Planets, Mariner 10 Venus/Mercury (2, to which Tombaugh adds “Discovered 9th planet, Pluto, on 18 Feb. 1930” to each). In overall fine condition, with a bit of edge toning to top border of one. R&R COA.
