While working on that something extraordinary dropped out of the final passage of numbers in the story of Djedi:

QuoteWikipedia on Djedi

Khufu stands up and orders: “Have Djedi assigned to a place within the palace of my son Djedefhor where he shall live from now on. His daily gainings be 1000 loaves of bread, 100 jars of beer, one neat and 100 bundles of field garlic.”

If we extract the numbers from the passage and multiply them together:

1,000 x 100 x 1 x 100 = 10,000,000

then multiply that number by itself and by 365 (as this is Djedi's daily gainings and there are 365 days in a year):

10,000,000 x itself x 365 days = 3.65 x 10^16

Divide by 2 = 1.825 x 10^16 If we assume that number is in Royal Cubits and convert to metres:

Divide by 1.91 RC to m = 9.55 x 10^15 metres

The current definition of a light year is 9.46 x 10^15 metres, so 9.55 x 10^15 metres is about 1% out from currently defined light year distance.

Why divide by 2? The loaves of bread Djedi consumes daily from the start of the story is half the amount provided to him at the end. If you understand a light year distance, you have an understanding of the speed of light as distance = speed x time. If these numbers do in fact provide a means to calculate a distance light travels in a period of time, an interesting piece is that the distance light travels in a day is 5 x 10 ^13 RC. Given how simple this number is to express, it makes me wonder if the Royal Cubit was actually defined in terms of the speed of light.