What is the first hour of a lunar day? What was the last hour?

The first hour of the lunar calendar is midnight, and the last hour is midnight.

Explain in detail:

The sub-time corresponds to 23: 00-0 1: 00, and the boundary of a day is 24: 00 or 00: 00, so the first half of the time belongs to the previous day and the second half belongs to the next day.

"New Tang Calendar": "The ancient calendar divides the day and begins at midnight." Therefore, every day begins in the early morning and ends in the late night.