Visitors pose for a photo with former NASA astronaut Paul Richards at the Earth Day event on Thursday, April 19, 2018 at Union Station in Washington, D.C. Photo Credit: (NASA/Aubrey Gemignani)
Visitors pose for a photo with former NASA astronaut Paul Richards at the Earth Day event on Thursday, April 19, 2018 at Union Station in Washington, D.C. Photo Credit: (NASA/Aubrey Gemignani)