Laran is the satellite of Revona. Its composition is strikingly dissimilar to Revona: no atmosphere, a solid crust and interior of carbonaceous material.
Scientists had installed permanently stationed geoseismic monitors that have recorded no internal activity, only occasional meteoritic bombardment.
The above suggest that Laran is a captured body and has an age measurable in eons.
Laran is the site of the Revonan helium conversion facility which provides the liquid helium 3 required for supercooling the reactive coils of the hypo-gravimetric power generators used on Arrakis.
Sources: Dune Encyclopedia?,
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