# The geography of Arrakis

Does the geography of Arrakis make sense?

I'm always a bit confused about how big the planet is, and where everything fits. According to the map, every point of interest is above the 60 degree north latitude, but then everyone says that "the south polar regions are off-limits". But... the south pole would be extremely far away! There's like... an entire planet between Arrakeen and the south pole.

Also, from the map it seems that Arrakeen and Sietch Tabr are almost 90 degrees of longitude apart. How did Paul and Jessica conveniently end up very near to it after their escape?

How did Paul make it to Harg Pass to bury his father's skull in the middle of a razzia, when that's actually really far from both Arrakeen and presumably from where the attack was mounted? In that region the Fremen can't use worms, so that's a lot of area to cover in a Harkonnen-controlled region.

And finally, when Paul does his first worm ride, don't they make it from Sietch Tabr to Cave of Birds in one single ride? That also looks like a pretty impressive distance.

Well, the latter points are mostly minor head-scratches, but the leap from "north pole: safe" to "south pole: out of bounds, but we sometimes fly patrols there" has always confused me the most. Where is all the rest of the planet?

• @DVK: Well, it has 0.9g gravitation. That should put certain bounds on the size of the thing. Commented Mar 15, 2013 at 16:01
• Radius is proportional to surface gravity and inversely proportional to density. So the most extreme case would be a planet consisting mostly of Iridium, 4 times the mean density of Earth, which would need to have a radius (and thus circumfence) 4.5 times smaller than Earth to get a gravity of 0.9g. That would still make Arrakeen and Sitech Tabr over 2000km apart. Commented Mar 15, 2013 at 16:49
• The Dune Wikia page ( dune.wikia.com/wiki/Arrakis/DE ) list the radius as 6128 km. It is unsourced, but probably taken from the Dune Encyclopedia, which is not written by Herbert, but which was not written totally without his collaboration and approval. Commented Mar 15, 2013 at 17:04
• Also: Carthag is "some 200 km northeast across the Broken Land" from Arakeen. (according to Dune) Commented Mar 15, 2013 at 17:19
• @horatio He definitely did not approve of everything in the Dune Encyclopedia! Anyway, I can't seem to find the page in the Encyclopedia that mentions the 6128 km, but it does say "Arrakis has a density of 4.95 g/cm³ an an acceleration due to gravity of 864 cm/sec²". Then the math is easy. Commented Mar 15, 2013 at 22:49