Captain Tom Moore might be the unlikeliest pop-chart topper since, oh, the Singing Nun back in 1963. But even before he hit No. 1 in the U.K., last week, Moore was probably familiar to you. The 99-year-old widower had Zimmer-framed his way into our hearts earlier this month by walking back and forth in his garden in Bedfordshire, England, 100 times to raise money for his country’s chronically needy National Health Service, which has been tested more than usual of late. Through pledges, Moore had hoped to raise £1,000, or around $1,250, by his 100th birthday, on April 30; by the time he was done walking, donations had reached $15 million. That figure has since climbed to around $34 million. Even on his concluding laps, the World War II veteran was moving at a steady clip and clearly could have kept going.

By then, Moore—still pre–pop stardom—had become “Captain Tom” to one and all. “He’s a one-man fundraising machine,” said Prince William, “and God knows what the final total will be. But good on him, and I hope it keeps going.” For his part, William’s brother, Harry, found him “utterly amazing. It’s not just what he’s done but it’s the reaction that people have had as well. Just wonderfully British.” Moore gave few interviews, but the handful he did grant revealed a modest, charming optimist. On Good Morning Britain,he thanked the health workers on the front lines and assured everyone that, “without doubt, things will get better.... Please remember that tomorrow is a good day.”