WASHINGTON — Sonia Sotomayor, her family and friends gathered at the Supreme Court today for her swearing-in as the court's first Hispanic, third woman and 111th justice.

Chief Justice John Roberts will preside today at two ceremonies that will make Sotomayor a high court justice.

Sotomayor, 55, has been a federal judge for 17 years. President Barack Obama nominated her in May to take the place of Justice David Souter, who has retired. The Senate confirmed Sotomayor's nomination Thursday.

Before she can begin her new job, though, she has to take two oaths.

In a private ceremony in the justices' conference room, Roberts will administer an oath the Constitution requires of all federal officials, to "support and defend" the Constitution. Then, in a public ceremony expected to be aired live on some cable networks, he will give Sotomayor a second oath in which she pledges to "administer justice" fairly and impartially, as prescribed by a 220-year-old federal law.

After that, the newest justice can get to work, although the court won't hear arguments until Sept. 9.

The entire court will convene a day earlier, however, for a formal ceremony to welcome Sotomayor.