NASA Administrator Bill Nelson attends a press conference at the U.S. ambassador's residence, in Mexico City, Tuesday, April 23, 2024. Nelson and Deputy Administrator Pamela Melroy, both former astronauts, spent two hours chatting with President Andrés Manuel López Obrador Tuesday. (AP Photo/Marco Ugarte)
NASA Administrator Bill Nelson and Deputy Administrator Pamela Melroy attend a press conference at the U.S. ambassador's residence, in Mexico City, Tuesday, April 23, 2024. Nelson and Melroy, both former astronauts, spent two hours chatting with President Andrés Manuel López Obrador Tuesday. (AP Photo/Marco Ugarte)
Deputy Administrator Pamela Melroy and NASA Administrator Bill Nelson attend a press conference at the U.S. ambassador's residence, in Mexico City, Tuesday, April 23, 2024. Nelson and Melroy, both former astronauts, spent two hours chatting with President Andrés Manuel López Obrador Tuesday. (AP Photo/Marco Ugarte)