 | Although the tablets were not dated, Stephenson Yau and Hunger noted that they
covered consecutive months.
|
| They gave many observations of the moon, but, as the moon comes to more or less the
same part of the sky every 29½ days, it is not much use for pinning down a particular
date.
|
| Some observations noted the positions of 2 or more planets at the same time.
Planets travel much slower than the moon. Mars takes about 2 years to orbit the sun,
Jupiter 11 years and Saturn nearly 30 years.
|
| Comings together of planets in the sky are much rarer events and one can begin to
work out a date with some confidence, given the positions of several planets.
|
| We will look at 2 sets of observations that give a
flavour of how Stephenson Yau and Hunger pinned down the dates.
|
| Having established that the Babylonians made these observations in the autumn of
164 BCE, how can we be sure the comet was Halley's?
|
| While running the simulations for the comet we realised that there was another significant event. |
