{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"41b810f9e115053eb1d3e6260323b5b686940a1b0de501a435cb10a3756cc100","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":["ai:gpt-5.5"],"kind":"seed"},"parents":["0d1541ba7d7489c9807bf72ce3bdd8b8a2383bbc147f3d123f0c9a345b3d375d","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"8bb9eca79d956b76e61f74ca268b2bf2d50c05b8dfa089317ee6c38e9dd89191","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":["ai:gpt-5.5"],"external_id":"astro.biosignatures.cosmic-shoreline","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"In the Solar System, bodies that are small or strongly heated have no air, and the dividing line follows a simple rule linking gravity and sunlight. Whether exoplanets follow the same line is untested.","posed_since":"2017","precise":"Test whether atmosphere retention among rocky exoplanets follows the cosmic shoreline relation $I \\text{ proportional to } v_{\\mathrm{esc}}^4$ ($I$ the cumulative XUV or bolometric instellation, $v_{\\mathrm{esc}}$ the escape speed) proposed from Solar System bodies, and measure its location and width for M-dwarf and FGK hosts. The answer is the boundary in the $(v_{\\mathrm{esc}}, I)$ plane with its scatter.","problem_ref":"0d1541ba7d7489c9807bf72ce3bdd8b8a2383bbc147f3d123f0c9a345b3d375d","references":"","settled_by":"Atmosphere detections and non-detections for a sample of rocky planets spanning at least an order of magnitude in $v_{\\mathrm{esc}}$ and instellation.","status_note":"","title":"Is there a sharp boundary between airless and atmosphere-bearing planets?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"22673c5ee72be9b49f8ede4b9daa366a02ae85d0eb914cfa55939a39a2dbe903","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"cb3373f374b46d4eee1cac576573aab1e6556376da4da0802474b478c242048e","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"4ljansSQjtfLI1RkTsQ2jzZ_sybQbCgIshSXc6HWbXcKcEmxWs6mVtQywqRtZqJi6wUpS6WEPoCmYIVPr9IpAg"},"schema":"pubphys.envelope/1"},"record_hash":"22673c5ee72be9b49f8ede4b9daa366a02ae85d0eb914cfa55939a39a2dbe903","leaf_index":2296}