On this year’s Day of Remembrance, we honor the brave men and women of NASA who lost their lives in our Nation’s eternal quest to expand the boundaries of human potential. The dedication and sacrifice of the Apollo 1, Challenger, and Columbia crews, remind us of the true bravery and resiliency of the American spirit, and the challenges we boldly face to reach higher for all mankind. America’s leadership in space is not without cost, but we have met tragedy with perseverance and challenge with achievement. We will not forget the contributions of our great American heroes as we build on their legacy to reach vast and exciting frontiers.