The Investiture is a ceremony in which a new Supreme Court Justice, already sworn onto the court, is ceremonially welcomed:

The Investiture Ceremony

On June 23, 1969, the Court closed its last scheduled sitting with a formal Courtroom ceremony in which retiring Chief Justice Earl Warren administered a combined oath to incoming Chief Justice Warren E. Burger. Under Chief Justice Burger, the Court began to hold special sittings to receive the commissions of newly appointed Justices. The first ceremony of this kind was held for Justice Harry A. Blackmun on June 9, 1970. During this special ceremony, referred to as the investiture, the Chief Justice generally administers the Constitutional Oath privately to the new Justice in the Justices’ Conference Room, the commission is presented and read aloud in the Courtroom and the Chief Justice administers the Judicial Oath in the Courtroom. Burger also started a tradition of having the new Justice sit in the historic John Marshall Bench Chair at the beginning of the ceremony.

There is a tradition of the new Justice then walking down the Supreme Court steps, as this video of Justice Kagan shows:

Brett Kavanaugh’s Investiture ceremony is on Thursday, November 8. But due to security concerns, it will not be broadcast live and he will not walk down the courthouse steps.

AP reports:

The Supreme Court says new Justice Brett Kavanaugh won’t take the traditional walk down the courthouse steps after his ceremonial installation on the court because of security concerns.

Kavanaugh’s investiture ceremony is scheduled for Thursday morning in the courtroom. It is customary for a new justice to walk down the 44 marble steps in front of the building, accompanied by the chief justice. The moment provides a chance for news organizations to photograph the justice, since the courtroom event is closed to cameras.

Court spokeswoman Kathy Arberg said Friday that the change is being made “out of an abundance of caution due to security concerns.”

This is not surprising given the unhinged and dangerous behavior shown by opponents of Kavanaugh’s confirmation, including disruption of the hearings, confrontations with Senators in hallways, and attempts to storm the Supreme Court itself.