NASA Administrator Jared Isaacman has weighed in on a 20-year-old space debate and said Pluto should be considered a planet again. In a hearing of the Senate subcommittee on Commerce, Justice, Science, and Related Agencies, Mr. Isaacman said Tuesday, “I am very much in the camp of ’make Pluto a planet again.’” The International Astronomical Union, which defines celestial objects and bodies and decides their official names, declared in 2006 that Pluto was not a true planet but was instead a