Due to its almost +90° declination, Polaris practically cannot be seen from the south of the equator, and the fact is consistent only with the spherical Earth model. There is a prevalent myth in the flat-Earth community that claims Polaris is sometimes visible from the south of the Equator. The origin of the myth was an erroneous interpretation of a news article by flat-Earther Samuel Rowbotham, 1½ centuries ago.
The myth started from an article in the “Times” of May 13, 1862, describing captain’s log of the ship Sir George Grey, from the Cape of Good Hope, South Africa to London, England. It was reported that the southern cross and Polaris were simultaneously visible at midnight, April 19, on lat 23°53′ dan long 35°46′. The problem is that the coordinate was specified without sign, and it was unclear whether it was north or south of the equator, as well as east or west of the meridian.
Flat-Earther Samuel Rowbotham read the article and made an erroneous inference that the observation occurred south of the equator. The myth spread to other flat-Earthers like William Carpenter. Today, the myth is popularized again by unscrupulous flat-Earther Eric Dubay.
On a map, we can plot all the four candidates of the coordinate mentioned in the article, and decide if the position is plausible for the observation to take place:
- Off the shore of Mozambique: not plausible as it was not in the route of the ship.
- Off the shore of Brazil: not plausible as it was not close to the route of the ship.
- In the Red Sea: not plausible as the Suez Canal is not yet operational at that time.
- In the North Atlantic Ocean: the only plausible location.
Using Stellarium, we can determine how the stars appeared at the time, and the most plausible location, and indeed, Polaris and Crux were visible at the same time. We can conclude the observation was made comfortably north of the Equator, not south of it, as claimed by Rowbotham.
The origin of the myth was simply a 1½ centuries-old error. There was no attempt from the flat-Earth community to verify the facts. If anyone bothered to check it, then it should be easy to understand that Polaris is practically not visible south of the Equator.