Acting NASA Administrator Robert Lightfoot gives remarks at the graves of Apollo 1 crew members, Virgil Grissom and Roger Chaffee, during a wreath laying ceremony as part of NASA's Day of Remembrance, Thursday, Jan. 25, 2018, at Arlington National Cemetery in Arlington, Virginia. Wreaths were laid in memory of those men and women who lost their lives in the quest for space exploration. Photo Credit: (NASA/Bill Ingalls)