The charitable sector should hope that billionaire Jared Isaacman keeps seeking new adventures. Isaacman, who turned a payments-processing firm he started as a teenager into a multibillion-dollar company, periodically indulges his passion for aviation with head-turning flights. Each time, a prominent charity has joined the ride—and the stakes keep getting bigger. In 2009, Isaacman set a speed record for flying around the world in a light aircraft, raising tens of thousands of dollars for Make-a-Wish in the process. Last September, he took both his flying and his philanthropy to a much higher level. Isaacman led the first all-civilian trip to space, accompanied by a physician assistant, a community-college professor, and a data engineer. Isaacman paid for and commanded the SpaceX flight, known as Inspiration4, and he vowed to donate even more than the cost of the flight to St. Jude Children’s Research Hospital. Isaacman and his wife, Monica, personally donated …