Washington — Judge Ketanji Jackson will be sworn into office as an associate justice on the Supreme Court, Thursday noon. This is the official time that Justice Stephen Breyer’s retirement becomes formal, the court announced Wednesday. She will be the first Black woman on the high court.

Chief Justice John Roberts will administer a constitutional oath at the swearing in ceremony for Jackson. Breyer, who she clerked for, will administer a judicial oath. In April, the Senate confirmed Jackson as a Washington federal appeals court judge.

In a letter to President Biden, Breyer, 83 said that his retirement would be effective at noon on Thursday. This brings to an abrupt close his 28-year tenure as a judge.

Breyer will be leaving the Supreme Court after a term filled with blockbuster cases. The Supreme Court’s decision to overrule Roe V. Wade on Friday was the most significant. Other notable decisions include rulings that expanded gun rights and favored religious rights, which were the first in a decade.

On Thursday morning, the court will announce the two remaining opinions. The dispute about the Environmental Protection Agency’s authority over greenhouse gas emissions from power stations and the challenge to the Biden administration’s attempt to end the “remain in Mexico” policy.

Breyer wrote to Mr. Biden Wednesday, “It has been a great honor to participate in the effort to preserve our Constitution and rule of law.”

In 1994, former President Bill Clinton appointed Breyer to the Supreme Court. He announced in January that he would resign at the end his term. This gave Mr. Biden an opportunity to make his first appointment on the high court. In February, the president named Jackson his nominee and the Senate approved her nomination in less than two months.