The United States space agency recently marked the loss of a very important person to America’s early space efforts. NASA mathematician Katherine Johnson died earlier this month at the age of 101. She was an African American woman who is credited with breaking race barriers by working in NASA’s early space program. “Our NASA family is sad to learn the news that Katherine Johnson passed away this morning at 101 years old,” NASA Administrator Jim Bridenstine wrote on Twitter. “She was an American hero and her pioneering legacy will never be forgotten,” he added. Johnson received the Presidential Medal of Freedom from former President Barack Obama in 2015. At the time, then-NASA Administrator Charles Bolden praised Johnson. He said, “She’s one of the greatest minds ever to grace our agency or our country.”