eugene cernan was part of apollo 10.was on the crew of apollo 10 which got almost to the surface of the moon, but not quite. it was a test run. they called it, as you can see up here, the brochure celebrating the successful mission. it was the dress rehearsal for the moon landing. one thing i love is a letter that eugene cernan wrote to his mother the night before he left on the apollo 10 mission. it says, "dear mom, as you are reading this now, god willing, we are on our way and almost to the moon. mom, i have wanted to write this to you to say i love you very much and always will. i want you to be happy and excited about this flight as i am. it has to be the most challenging adventure of my whole life. you know i would never go anywhere or do anything that was deliberately dangerous. i want to go on this mission so very much. nothing of this nature is without a little apprehension. but this makes the reward even more meaningful. think of us when you look up at the moon at night. take care. i love you. be proud, happy,