How long will flags be at half-staff? Here's what to know after Jimmy Carter's death

President Joe Biden announced Monday that a national day of mourning will be held in early January following the death of former President Jimmy Carter, who died Sunday at age 100 in his hometown of Plains, Georgia.
The national day of mourning will be Thursday, Jan. 9, Biden said. In addition to the national day of mourning, effective immediately, all flags were ordered to be displayed at half-staff at the White House and on all public buildings and grounds, all military posts, naval stations and naval vessels.
How long will flags stay at half-mast and half-staff following Carter's death?
Here's what to know.
Jimmy Carter: The complex history of Joe Biden's decades-long friendship with the former president
Why are flags at half-staff?
In announcing the national day of mourning, set for Jan. 9, Biden also said all flags will be displayed at half-staff at the White House and on public buildings and grounds. Flags are also at half-staff at all military posts, naval stations and half-mast on naval vessels.
"I also direct that, for the same length of time, the representatives of the United States in foreign countries shall make similar arrangements for the display of the flag at half?staff over their embassies, legations, consular offices, and other facilities abroad, including all military facilities and naval vessels and stations," Biden said in a statement Sunday.
Private companies and citizens can also choose to display flags at half-staff.
How long will flags stay at half-staff?
The White House ordered public flags to be displayed at half-staff for a period of 30 days from Carter's day of death, who died Sunday.
What's the difference between half-staff and half-mast?
Flags are flown at half-mast on ships and at naval stations. On shore, flags are flown at half-staff, meaning the flagpole is attached to a building or stuck in the ground.
What are Jimmy Carter's funeral plans?
Public memorial observances for Jimmy Carter will take place in Georgia and on Jan. 9 at the Washington National Cathedral in Washington, D.C., according to the White House and the Carter Center.
In a statement, Biden said he would order an official state funeral for Carter, the 39th president. His body will lay in state at the Capitol, as have other presidents.
Biden also declared Jan. 9 as a national day of mourning.
Carter has previously said he will be buried in Plains, Georgia, his hometown. His wife, former first lady Rosalynn Carter, was also buried in Plains after her death in 2023.
This article originally appeared on USA TODAY: Why are flags at half-staff, and how long will they stay there?