Today it's Sunday. 7 days ago it was Sunday. 7000 days ago it was Sunday. But what about 70,000 days ago, 700,000 days ago, and 7 million days ago? Our current 7-day week cycle has not continued unbroken forever. So my question is, when did our current 7-day week cycle begin? Note that I'm not asking when any 7-day week cycle was invented, but rather the specific cycle we're still on.
Here is what Wikipedia says:
The continuous seven-day cycle of the days of the week can be traced back to the reign of Augustus; the first identifiable date cited complete with day of the week is 6 February AD 60, identified as a "Sunday" (as viii idus Februarius dies solis "eighth day before the ides of February, day of the Sun") in a Pompeiian graffito. According to the currently-used Julian calendar, 6 February 60 was, however, a Wednesday. This is explained by the existence of two conventions of naming days of the weeks based on the planetary hours system: 6 February was a "Sunday" based on the sunset naming convention, and a "Wednesday" based on the sunrise naming convention.
So February 6, 60 AD is the earliest identifiable date with a day of the week cited with it, but this was based on sunset naming convention, rather than the sunrise naming convention we use today. So what is the earliest identifiable date with a day of the week cited with it that is based on the sunrise naming convention?