My understanding (which may need correction!) is that the concept of a day of 24 equal length hours is fairly recent (a thousand or so years), except among astronomers. Before that, non astronomers divided daylight into 12 equal 'hours' and night also into 12 hours, with day and night hours only being equal at the equinoxes.
Does the naming of the weekdays precede or postdate the concept of a widely accepted 24 hour 'day' which contains both daytime and nighttime?
Regards to all
Bob Berghout School of Mathematical & Physical Sciences University of Newcastle NSW2308 Australia