U.S. Vice President Mike Pence gives commands to a rover nicknamed "Scarecrow" as NASA Mars Exploration Manager Li Fuk, left, Mars Curiosity Engineering Operations Team Chief Megan Lin, JPL Director Michael Watkins, and daughter of Mike Pence, Charlotte Pence, right, look on, Saturday, April 28, 2018 in Pasadena, California. Scarecrow is used to test mobility of rovers on Mars. Photo Credit: (NASA/Bill Ingalls)