 The first satellite,
Explorer 1, still went into space without solar cells, since it was a quick, less-than-ideal solution after the start of the Sputnik to show the American public that America's scientists could also start a satellite.The actual scheduled satellite project, Project Vanguard, successfully put a satellite named Vanguard I in orbit around Earth on March 17, 1958.Over the objections of the Navy, which still thought that solar cells were not a mature technology, this satellite had four solar cells on its outer hull, due to the persistent work of Ziegler, which powered the instruments and performed their duties reliably for more than seven years.