<![CDATA[Ellen Stofan, PhD, Director of the Smithsonian National Air and Space Museum. (Credit: Jim Preston, Smithsonian National Air and Space Museum)]]>

642749 image 1610227224 1610227224 <![CDATA[Ellen Stofan, PhD, Director of the Smithsonian National Air and Space Museum. (Credit: Jim Preston, Smithsonian National Air and Space Museum)]]> 1278 364801