My noisy pack of loyal readers will recall that last August I recounted how the ancient Greeks first blamed the searing heat of the northern summer on the rising of Sirius next to the sun. Sirius is the star of canines everywhere, but me in particular — given it is the brightest star in the universe.
In our southern summer, Sirius sits right overhead at night, in the constellation of Canis Major, while in the Northern Hemisphere summer it can’t be seen in July and August, because it rises in the morning too close to the sun.
Apart from prompting the Greeks to coin the term ‘dog days’, the dog star also prompted the ancient Egyptians (long before the Athenians were thinking about these things) to figure out the need for today, February 29, to be inserted into the calendar. The Egyptians came up with the need for a leap year, but it was centuries before everyone agreed on how to fix it.
The Egyptian astronomers first realised the coincidence of Sirius appearing in the dawn sky — around the time of the annual flooding of the Nile — some 2300 years ago.
The Egyptians thought fondly of Sirius, as they should have, because its appearance was linked to this annual flooding and the rich silt it spread over their farmlands, enabling their civilisation to survive.
Those early astronomers started tracking the exact time at which Sirius could be seen again, rising just before the sun in late August. After some years of doing this, they realised their 365-day calendar didn’t quite work because the solar year took 365-and-a-quarter days — and that this could eventually cause a slow drift in the seasons because the calendar didn’t match the habits of the sun.
The Boss tells me that, back in 1866, some German scholars unearthed the Tanis Stele, a seven-foot limestone slab bearing a detailed inscription in Egyptian and Greek of a decree by the pharaoh Ptolemy III. It was called the Canopus Decree because of the ancient city where it was found.
The decree has been dated to 238 BC and, among other matters, Ptolemy issued instructions about the Egyptian calendar. He announced that “the seasons should always correspond to the established order of the universe” and said he didn’t want winter festivals eventually being celebrated in summer, “as the sun changes by one day in the course of four years”.
Ptolemy announced that from then on, in honour of the gods, one festival day should be added in every four years to correct this defect in the seasons. Despite ordering that a copy of the decree be erected in every major temple, his instructions were ignored, possibly because the priests controlling the calendar thought adding an extra day every four years was just too untidy, which it is.
And they must have worried about anyone born on February 29 having a birthday only every four years, which is worse than having a birthday the week after Christmas.
Anyway, The Boss says that when the Romans annexed Egypt two centuries later, in 30 BC, they found the Egyptians persevering with a 365-day calendar, even though it was the Egyptians who inspired the Julian calendar that the Romans were using in the first place.
It was the Roman Emperor Augustus who ordered the Egyptians to bring the leap day — the idea they had first come up with — back into their calendar. And here we are. Woof!