Also, large bodies are more spherical than in US1, Much more spherical, the large bodies in US2 have more faces, 32768 faces, whereas the large bodies in US1 had 1296 faces, though once you type in the model "sphere", "planet", :moon", or "ball", you get a "sphere" with 2304 faces, all using a 1x1 scaling ratio.
The bodies in US@ are MUCH better, all credit goes to Georg for the improvement, though it's still not enough, besides the fact that the new bodies use a 2x1 scaling ratio, which is more uniform.
Each face of the large bodies takes up 1.4 degrees of their surface volume, and since a circle has 360 degrees in circumference, the outline of each large body in US2 is 256 sided, which is not quite enough, yet either 512x256 or 1024x512 divisions would be better, a 512x256 body would have a 512 sided outline, and a 1024x512 body would have 1024 sides on its outline, both would have each face within 1 degree of its surface volume, and therefore would pass the test for roundness.
A 512x256 body has 131072 faces, and a 1024x512 body has 524288 faces, and both would be indistinguishable from a perfect sphere, though the only imperfections we need would be the oblateness and geology.
Each body currently has 32768 faces, while a lot, is still not enough, today's computers can handle a lot more than 32768 faces.
Go download Blender and click "UV Sphere", and you'll have an idea.