Regolith With Latitude
January 3rd, 2026: and the last full moon in a series of four consecutive supermoons—those times when our satellite, fully lit, hews a little closer and looms larger in the sky. At its perigee, a supermoon will appear around 7% bigger, and 15% brighter than a more workaday moon.
If you have been traveling far north or south from home for the December holidays, a full moon may also seem different in other ways.
Our moon always shows the same face, and the same phase, to everyone on the good Earth: but it is not always the same way up. Travel far enough away from home, and the moon will appear rotated compared to one’s expectation, or even upside-down.
The moons above show how it might appear to Parisians,1 a common default. The Man in the Moon stands upright; Tycho crater, the bright splatter with its distinctive rays, sits on the moon’s bottom. If you see a rabbit in the moon, its ears are flattened down.
This is the moon you’ll see in Vancouver, Vienna, Volgograd or Ulaanbaatar, which all sit at a latitude of 48–49 degrees north.
But if travel to the southern hemisphere, the moon will be just as bright and as big, but down-side up. In Adelaide, Buenos Aires, or Cape Town,2 Tycho is near the top; the Man in the Moon stands on his head; the rabbit will be upright and the ears (the Sea of Fertility and Nectar) perk alert, unafraid and upward.
To predict how the biggest, brightest moon will look wherever you are, consult the diagram above. Pull the tab to choose your locale.
For more detailed assays of lunar appearance, refer to cousin Ernie Wright et al.’s marvelous interactive guides to the phases and librations of this year’s moon, from which our diagrams are drawn; available in both a north-biased, Borealist framing, and commendably, a southern, Austral alternative.
~Patrick Moores-Law
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One might expect scientific depictions of the moon to have been worn this eurocentric bias too, but while Parisians do believe – in this case somewhat defensibly – that the world revolves around them, their lunar illustrations have long portrayed a far more alien perspective than that of fair city.
For centuries, French publishers based their stock lunar illustration images on derivatives of Giovanni Cassini’s 54cm copperplate, crafted in Paris in 1679 – or rather the mass-produced version, shown below, distributed for the July 1692 lunar eclipse.
Figure 1. Cassini’s hit moon pic, depicting a rabbit (l.) fleeing the Shoggoth in the Moon (r.). Cassini liked his moon pics south-up and with the lunar axis cranked 30 degrees clockwise, placing his apparent location somewhere in Antarctica. Because of its prominence, this curious image was endlessly reprinted, notably in that notoriously shoddy statist rip-off johnny-come-lately, the Connaissance des Temps almanac (published continuously since 1679 and they still haven’t got the hang of it.).
Cassini’s popularized lunar snapshot, selenographer Ewen A. Whitaker writes, “formed the basis of numerous [French] maps of ever decreasing accuracy and aesthetic appeal” – p.100, “Mapping and Naming the Moon”, Cambridge University Press (1999).
South-up maps of the moon were common among early astronomers since that’s how the moon looks through an uncorrected Newtonian telescope. But times change. In 1961, under pressure from increasingly irritated astronavigators, the International Astronomical Union conceded, in French, that new moon maps for direct exploration purposes, could be north-side up. Sneakily, though, they also added that all future moon craters should be named after astronomers or prominent scientists. Note well that the astronomers didn’t have to be prominent. Or even good at drawing. ↩
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Why do the major cities on the 49th northern latitude all begin with an urceolate letter, while the major cities on the southern latitude are so abecedarian? Officially, this is coincidence—but see also Ἡρόδοτος, “Prince Cadmus and The Bi-Hemispheric Toponymic Compromise,” Almnck. Vol. 4440, ii.3. ↩