English: President Barack Obama waves hello as he exits of Air Force One along with Senator Bill Nelson after landing at the NASA Kennedy Space Center in Cape Canaveral, Fla. on Thursday, April 15, 2010. Obama visited Kennedy to deliver remarks on the bold new course the administration is charting to maintain U.S. leadership in human space flight. During a speech at the center, President Obama said, "As president, I believe space exploration is not a luxury, not an afterthought, an essential part of the quest."