There are 86 notches on the tablet, a number that has two special meanings. First, it is the number of days that must be subtracted from a year to equal the average number of days of a human gestation. This is no coincidence, says Dr Rappenglueck. It is also the number of days that one of Orion�s two prominent stars, Betelguese, is visible. To ancient man, this might have linked human fertility with the gods in the sky.