So far there are three night-sky observations which do not fit with the Flat Earth Model ("multiple, layered, counter-rotating, gear-driven, disc-like star-systems", or MLCRGDDLSS):
1. Star-trails are circular, not elipitical (there is no perspective distortion)
2. Star-trails form a smooth, continuous pattern (there are no sudden deviations in course) and
3. The Milky Way is a continous band from north to south (it never splits in two).
Now here is a fourth:
If there is one MLCRGDDL star-system sitting over The North Pole, then all observers in The Northern Hemi-disc will see the stars rotate around a point which is due North (by the compass).
Now that point is, more or less, the star known as Polaris (The Pole Star) and it is accepted that this is north and has been helping sailors navigate in The Northern Hemispeher for centuries.
(So far, so good.)
But ...
If there is also another MLCRGDDL star-system sitting somewhere south of Australia then it cannot be sat above The South Pole because this does not exist on a Flat Earth (lines of longitude continue to diverge forever, just as on The UN flag.)
Therefore ...
Observers at different longitudes in Australia - and it is a very wide continent so there is a wide range of longitudes to choose from - will see the star-system rotate around a point which is at a different compass bearing (i.e. not always due south).
So how come nobody has ever, to my knowledge, reported such an observation?
An observation which would clearly disprove the existance of The South Pole.
An observation which would prove that Amundsen, Scott, Oates, et al. were lying when they said that they walked there.
An observation which would prove that all of the astronomers have been lying to us all this time.
An observation which would be of almost infinite benefit to the Flat Earth Community as it would prove their theories.
So: have any of the Flat Eathers out there ever made such an observation ("he says, expecting the answer no" *)?
And if not, then you should all club together and buy a ticket to Australia ASAP and get observing!
(And I may ask my pal in Sydney to take a road trip to Perth sometime and do the measurements himself!)
So: four observations which do not make sense if The World were flat ...
Please explain.
* Monty Python's "Cheese Shop" sketch - "SHUT THAT BLOODY BAZUKI UP!"
Some edits, in blue.