Fun fact:

The 20th Amendment moves the date of inauguration from March to "noon on the 20th day of January." Under the Constitution, the old president continues to hold full power through 11:59:59, and then power shifts at noon. Article II, Section 1 requires that the new president, before executing any duties, take a prescribed oath or affirmation. To avoid a constitutional power vacuum, the Inauguration Day program is certain to schedule the swearing in for as close as possible to noon.

However, noon on the east coast is (edit) 9AM on the west coast. So there's that.

Fun fact:

The 20th Amendment moves the date of inauguration from March to "noon on the 20th day of January." Under the Constitution, the old president continues to hold full power through 11:59:59, and then power shifts at noon. Article II, Section 1 requires that the new president, before executing any duties, take a prescribed oath or affirmation. To avoid a constitutional power vacuum, the Inauguration Day program is certain to schedule the swearing in for as close as possible to noon.

However, noon on the east coast is 10AM on the west coast. So there's that.

Fun fact:

The 20th Amendment moves the date of inauguration from March to "noon on the 20th day of January." Under the Constitution, the old president continues to hold full power through 11:59:59, and then power shifts at noon. Article II, Section 1 requires that the new president, before executing any duties, take a prescribed oath or affirmation. To avoid a constitutional power vacuum, the Inauguration Day program is certain to schedule the swearing in for as close as possible to noon.

However, noon on the east coast is 10AM on the west coast. So there's that.