Vande Hei and Acaba at Walt Whitman Middle School

NASA astronaut Mark Vande Hei speaks about his time onboard the International Space Station during a presentation to students at Walt Whitman Middle School, Thursday, June 14, 2018 in Alexandria, Va. Vande Hei and astronaut Joe Acaba answered questions from the audience and spoke about their experiences aboard the International Space Station for 168 days as part of Expedition 53 and 54. Photo Credit: (NASA/Joel Kowsky)