President John F. Kennedy spelled out the mission clearly in his 1961 speech committing the United States to send humans to the moon and back by the end of the decade. He left no doubt about the definition of success and laid out a clear vision.
Now, five decades after his challenge, a panel of space, science and engineering experts said in a stinging report that NASA does not have a goal.
While the future of the space agency may be unclear, its past missions produced some iconic images that gave us all a view of the world that makes it seems not quite so big, including newly released photos that include city lights at night.
Here's an Associated Press photo gallery with some of those images.