The planet is so remote that Canopus appears as just a very bright first-magnitude star.
It is composed entirely of helium in different phase states. From upper to lower:
A dense atmosphere of atomic helium covers lays depth of 70,000 meters. Temperatures there vary from 11°K (at the upper helium boundary) to 4.2°K (at the quasi liquid surface). The atmosphere was discovered by Daret of the Planetoscience Council on Arrakis (AG 14390)
Just beneath, the pressure is sufficient to alter the phase state of helium from gaseous to liquid and results to a pale blue sea of liquid helium.
At a depth of 3,900 meters, the liquid temperature reaches 2.6°K and the helium abruptly changes to the zero-viscosity helium 3 as the liquid helium passes through the tri-alpha transition. This transition is only a few meters thick and is characterized by high dynamic turbulence. Helium 3 from that zone is processed by a facility installed on the moon, Laran.
Finally, there is a solid central core of unknown composition, perhaps of helium existing in the supra metallic state.
Sources: Dune Encyclopedia?,
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