Today marks the fiftieth anniversary of John F. Kennedy's legendary clarion call to the United States, to invest its heart, hopes and mind in the exploration of space. An enduring message of audacity and spirit, it remains as rousing (and, arguably, as relevant) today as it did when Kennedy delivered it at Rice University in 1962.

"Many years ago," stated Kennedy, toward the end of his address, "the great British explorer George Mallory, who was to die on Mount Everest, was asked why did he want to climb it. He said, 'Because it is there.'"

Today, fifty years on, space is still there. The Moon, the planets, and new hopes for knowledge and peace are still there. And so we climb, because we humans are wanderers; because to flag in the face of a challenge as bold as space would be to deny our very nature; and because we must always push ourselves to dare mighty things.