{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"eb0f933946c3223f9361536864af86e410aa2c9a269282f26c11ad92f4e90b0e","created":"2026-10-03T07:18:03Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"81cac114f606d0ec1d3b3b58cf9bd7e4f853eb4b96f51f33b7dea6d487914949","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"classification","assisted_by":[],"external_id":"earth.ocean-worlds.titan-interior","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"Cassini measured how much Titan, Saturn's largest moon, is squeezed by Saturn's tides, and the large response was first read as a sign of a hidden global ocean. A 2025 reanalysis argues instead for a slushy layer of ice with pockets of water.","posed_since":"","precise":"Determine from Titan's tidal Love number $k2$, the tidal phase lag and the rotation state whether its interior contains a global liquid water ocean decoupled from the ice shell or a high-pressure-ice layer containing partial melt, and constrain the hydrosphere structure. An answer is an interior model that matches $k2$, dissipation and obliquity data and excludes the alternative.","problem_ref":null,"references":"","settled_by":"Independent measurements of Titan's tidal response and dissipation, for example from Dragonfly geophysics, together with consistent rheological models.","status_note":"Petricca et al. 2025 (Nature) argued that strong tidal dissipation in Cassini data precludes a global subsurface ocean.","title":"Does Titan have a global liquid ocean or a slushy interior?","topic_ref":"fce9705aed3acbaf66c27413ec3badd10cbd89376e3f1b6fc466396c06130caa"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"70211a1279ed34d107cd6eb64fccc9840668f6b1632cc9a785e7f2c345a591f0","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"26a79ba924ba2d259b34d7cd64e2e6e298f96d03dc5f21abd63e1dc55d074eeb","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"fS19BvCU3ICs42OSM2dWcEBbeKkZM_rvK7qariQtROjagCIKxfZ-E-mGHaUWKRX8DADLdbAw6HrXoAVjK81xDQ"},"schema":"pubphys.envelope/1"},"record_hash":"70211a1279ed34d107cd6eb64fccc9840668f6b1632cc9a785e7f2c345a591f0","leaf_index":1346}