The National Park Service strives to preserve and protect America’s great natural and cultural resources unimpaired for future generations. The places in our custody range from the depths of Carlsbad Cavern to the night sky, which stretches over all parks. Carlsbad Cavern and the Moon are both rocky worlds to explore. Both contain colossal and awe-inspiring features. And both are delicate environments where footprints from 50 years ago are still visible today.