How did ancient civilisations use observations of the Sun and Moon?

To build calendars and time agriculture

Why may an ancient monument's astronomical alignment no longer be accurate?

The precession of the Earth's axis has shifted sunrise and star positions

It reproduced the observed retrograde motion of the planets

The distance light travels in one year

The distances to stars are so vast that larger units keep the numbers manageable

It makes planetary distances small, manageable numbers

11questions. Pick an answer and you'll see why right away.

How did ancient civilisations use observations of the Sun and Moon?
Why may an ancient monument's astronomical alignment no longer be accurate?
What did the geocentric model place at the centre of the Universe?
What was the advantage of Ptolemy adding epicycles to the geocentric model?
What is one astronomical unit (AU)?
What is a light year?
How many light years are there in one parsec?
Why do astronomers use the light year or parsec rather than the AU for distances to stars?
Roughly how far away is the nearest star to the Sun?
Which best describes the orbits used in the early geocentric model before epicycles?
Why is the AU a convenient unit for the Solar System?