President Joe Biden announced Friday he was nominating Judge Ketanji Brown Jackson to become the first Black woman to serve on the U.S. Supreme Court. Biden nominated Jackson last year to the U.S. Court of Appeals for the District of Columbia. She previously served eight years as a district judge in D.C. federal court. She has also worked as a public defender and was a clerk under Supreme Court Justice Stephen Breyer. If confirmed, she would replace Breyer, who is 83. Jackson is 51 years old.