Celebrate the anniversary of Explorer 1, the first U.S. satellite, with NASA as we “Explore as One” with the materials below. Download the official Explorer 1 anniversary poster urging us to keep going in our explorations of Earth and beyond, get specs to print your very own small model of Explorer 1 with a 3D printer, print out an actual-size cutout of Explorer 1 to hold over your head and #ExploreAsOne or read a comprehensive history of Explorer 1 that helps put the science achievements into the context of the era.