As an expert in timekeeping and temporal definitions, I can provide some insights into the concept of a day and how it is measured. The question you've asked is quite specific and relates to the start of a new day at 12 am. To address this, let's delve into the standard definitions and practices used by various organizations and the general public.
Step 1: English Answer
The start of a day can be a matter of convention and depends on the context in which the question is being asked. For most people, the day starts at 12:00 am, which is also known as midnight. This is the point at which the date changes, marking the end of one day and the beginning of the next. However, there are different interpretations of what constitutes the exact moment when a new day begins.
The US Naval Observatory, which is one of the leading authorities on timekeeping, defines a day as starting at 12:00:00 midnight. This is in line with the common understanding that the day transitions from one to the next at the stroke of midnight. According to this definition, the last moment of a day is the final instant before the next day begins, which would be one second before 12:00:00 am. This precise measurement is crucial for various legal, astronomical, and operational contexts.
For instance, if we consider the scenario you've mentioned regarding the expiration of the NFL Collective Bargaining Agreement (CBA), if the agreement was set to expire at the end of a specific day, under the US Naval Observatory's definition, it would indeed expire one second after 11:59 p.m. on the given date. This is because the agreement would no longer be in effect as soon as the new day begins, which is marked by the first second of 12:00:00 am.
It's important to note that while the US Naval Observatory's definition is widely accepted, there are other ways in which the start of a day can be defined. In some cultures and legal systems, the day might start at a different time, such as sunrise or noon. Additionally, in computing and certain technical fields, the start of a day can be defined as 12:00:00 pm (noon) to align with the 24-hour clock system.
In conclusion, the concept of when a new day begins is not universally fixed and can vary based on the context and the specific definitions used by different organizations or individuals. However, for most practical purposes, including legal and astronomical contexts, the day is considered to start at 12:00:00 midnight, with the last second of the previous day being one second before this time.
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The US Naval Observatory defines a day as starting at 12:00:00 midnight. It ends at the last possible instant before the next day starts. Thus, if the question's specification was correct, the NFL CBA expired one second after 11:59 p.m. on Wednesday, March 2, 2011.read more >>