On this day in 1950, NASA astronaut Ronald McNair was born. He died during the launch of the Space Shuttle Challenger in 1986, age 35. In 1959, police were called to a segregated library when a Black 9-year-old boy trying to check out books refused to leave, after being told the library was not for Black people. The boy, Ronald McNair, went on to became an astronaut. The library is also now named after him. Ronald McNair was 9 when a South Carolina librarian told him he could not check out books from a segregated library in 1959. Refusing to leave, a determined McNair sat on the counter while the librarian called the police, as well McNair's mother. The police arrived, told the librarian to let the young boy have his books, and McNair walked out alongside his mother and brother. McNair went on to earn his Ph.D. in physics at MIT and became one of the first African Americans selected as astronauts by NASA, alongside Guion S. Bluford, Jr. and Frederick Gregory. McNair's first spaceflight was the STS-41B mission, aboard the "Challenger" shuttle. He successfully maneuvered the robotic arm, which allowed astronaut Bruce McCandless to perform the first space walk without being tethered to the spacecraft. On this day in 1986, the second space flight for McNair would be his last. He, along with six other NASA astronauts, were aboard the Space Shuttle Challenger when it exploded 73 seconds after takeoff in 1986. Everyone on board the shuttle was killed. Today, the library in South Carolina where McNair was refused books is named after the heroic boy determined to make a difference.