Apollo 16 moonwalker Charlie Duke signed 20'' x 16'' photo of the Phoenix Lander on Mars, with his thoughts of exploring the red planet as the next step in space exploration. Composed in black felt-tip, Duke writes in full, ''The challenge of Mars is going to be tremendous! To think about going there and building a station on Mars is going to be a challenging endeavor and I think we can do it. The human spirit wants to go to Mars and go out and explore. It will be another small step for man and another giant leap for mankind. / Charlie Duke / Apollo 11 CAPCOM / Apollo 16 Moonwalker''. Satin-finish photo is near fine.