Terrestrial Time
All these dates are in a uniform time scale such as Terrestrial Time. When converted to our ordinary solar time or Universal Time, which is decidedly non-uniform, via ?T, the dates would be about one day earlier. Because of this difference, these dates have no anniversary relation to historical dates and should not be linked to them. Furthermore, they are only astronomical dates, so they are given in the astronomical format of Year Month Day, which allows them to be ordered.