{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:CNXLXA6BDPZI7BWIZXTEK3GAHX","short_pith_number":"pith:CNXLXA6B","canonical_record":{"source":{"id":"1904.07727","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.EP","submitted_at":"2019-04-16T14:36:18Z","cross_cats_sorted":["astro-ph.IM"],"title_canon_sha256":"9453fc6d3da006821bbe67ff4361497b7ae7b61efb61e51dc2afe0e069e11835","abstract_canon_sha256":"5eb13a8835e91bb0000d25e28fcbd817e9904eeea383ea2e4f8bf39204f5df82"},"schema_version":"1.0"},"canonical_sha256":"136ebb83c11bf28f86c8cde6456cc03dc3d558f12a6132e80ea28ad792ee50d4","source":{"kind":"arxiv","id":"1904.07727","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1904.07727","created_at":"2026-05-17T23:46:52Z"},{"alias_kind":"arxiv_version","alias_value":"1904.07727v1","created_at":"2026-05-17T23:46:52Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1904.07727","created_at":"2026-05-17T23:46:52Z"},{"alias_kind":"pith_short_12","alias_value":"CNXLXA6BDPZI","created_at":"2026-05-18T12:33:15Z"},{"alias_kind":"pith_short_16","alias_value":"CNXLXA6BDPZI7BWI","created_at":"2026-05-18T12:33:15Z"},{"alias_kind":"pith_short_8","alias_value":"CNXLXA6B","created_at":"2026-05-18T12:33:15Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:CNXLXA6BDPZI7BWIZXTEK3GAHX","target":"record","payload":{"canonical_record":{"source":{"id":"1904.07727","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.EP","submitted_at":"2019-04-16T14:36:18Z","cross_cats_sorted":["astro-ph.IM"],"title_canon_sha256":"9453fc6d3da006821bbe67ff4361497b7ae7b61efb61e51dc2afe0e069e11835","abstract_canon_sha256":"5eb13a8835e91bb0000d25e28fcbd817e9904eeea383ea2e4f8bf39204f5df82"},"schema_version":"1.0"},"canonical_sha256":"136ebb83c11bf28f86c8cde6456cc03dc3d558f12a6132e80ea28ad792ee50d4","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:46:52.423169Z","signature_b64":"x0KmtfFHxzx3HhYAXOQ3hGduI27ksx/yi3P20zO+1zEHcRZ909s94LOWlh1DFYyn9Au+XAtMBp7o3DFRMI6sAw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"136ebb83c11bf28f86c8cde6456cc03dc3d558f12a6132e80ea28ad792ee50d4","last_reissued_at":"2026-05-17T23:46:52.422678Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:46:52.422678Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1904.07727","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:46:52Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"OYBSs0+rDLTaczNgchqe6p2yyyeubUz3XH4laDpNX/VFpTKugRZSaKVB1Ha6Qi1+TD5Mex7Cf2uqRvOhXOoPAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-04T17:31:17.628260Z"},"content_sha256":"dade612ff9704620acb30d634d201e1c056c10195d4fbd5555862fd598933978","schema_version":"1.0","event_id":"sha256:dade612ff9704620acb30d634d201e1c056c10195d4fbd5555862fd598933978"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:CNXLXA6BDPZI7BWIZXTEK3GAHX","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Using Cosmogenic Lithium, Beryllium and Boron to Determine the Surface Ages of Icy Objects in the Outer Solar System","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.IM"],"primary_cat":"astro-ph.EP","authors_text":"M.M. Hedman","submitted_at":"2019-04-16T14:36:18Z","abstract_excerpt":"Given current uncertainties in the cratering rates and geological histories of icy objects in the outer solar system, it is worth considering how the ages of icy surfaces could be constrained with measurements from future landed missions. A promising approach would be to determine cosmic-ray exposure ages of surface deposits by measuring the amounts of cosmogenic Lithium, Beryllium and Boron at various depths within a few meters of the surface. Preliminary calculations show that ice that has been exposed to cosmic radiation for one billion years should contain these cosmogenic nuclei at concen"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1904.07727","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:46:52Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"u5GvvyN1WQjefuIxWKtePG3Vv7+OTVio8VJp9ZNaFKbvZWtzCEYRgVPOtnfdjamHZ/J9CQxweadM/xelKG4BDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-04T17:31:17.628663Z"},"content_sha256":"76a1affd528f1fd55f9db2f0bf20fdf084bd4b0688ed98cab13111b843e3e279","schema_version":"1.0","event_id":"sha256:76a1affd528f1fd55f9db2f0bf20fdf084bd4b0688ed98cab13111b843e3e279"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/CNXLXA6BDPZI7BWIZXTEK3GAHX/bundle.json","state_url":"https://pith.science/pith/CNXLXA6BDPZI7BWIZXTEK3GAHX/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/CNXLXA6BDPZI7BWIZXTEK3GAHX/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-06-04T17:31:17Z","links":{"resolver":"https://pith.science/pith/CNXLXA6BDPZI7BWIZXTEK3GAHX","bundle":"https://pith.science/pith/CNXLXA6BDPZI7BWIZXTEK3GAHX/bundle.json","state":"https://pith.science/pith/CNXLXA6BDPZI7BWIZXTEK3GAHX/state.json","well_known_bundle":"https://pith.science/.well-known/pith/CNXLXA6BDPZI7BWIZXTEK3GAHX/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:CNXLXA6BDPZI7BWIZXTEK3GAHX","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"5eb13a8835e91bb0000d25e28fcbd817e9904eeea383ea2e4f8bf39204f5df82","cross_cats_sorted":["astro-ph.IM"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.EP","submitted_at":"2019-04-16T14:36:18Z","title_canon_sha256":"9453fc6d3da006821bbe67ff4361497b7ae7b61efb61e51dc2afe0e069e11835"},"schema_version":"1.0","source":{"id":"1904.07727","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1904.07727","created_at":"2026-05-17T23:46:52Z"},{"alias_kind":"arxiv_version","alias_value":"1904.07727v1","created_at":"2026-05-17T23:46:52Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1904.07727","created_at":"2026-05-17T23:46:52Z"},{"alias_kind":"pith_short_12","alias_value":"CNXLXA6BDPZI","created_at":"2026-05-18T12:33:15Z"},{"alias_kind":"pith_short_16","alias_value":"CNXLXA6BDPZI7BWI","created_at":"2026-05-18T12:33:15Z"},{"alias_kind":"pith_short_8","alias_value":"CNXLXA6B","created_at":"2026-05-18T12:33:15Z"}],"graph_snapshots":[{"event_id":"sha256:76a1affd528f1fd55f9db2f0bf20fdf084bd4b0688ed98cab13111b843e3e279","target":"graph","created_at":"2026-05-17T23:46:52Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"Given current uncertainties in the cratering rates and geological histories of icy objects in the outer solar system, it is worth considering how the ages of icy surfaces could be constrained with measurements from future landed missions. A promising approach would be to determine cosmic-ray exposure ages of surface deposits by measuring the amounts of cosmogenic Lithium, Beryllium and Boron at various depths within a few meters of the surface. Preliminary calculations show that ice that has been exposed to cosmic radiation for one billion years should contain these cosmogenic nuclei at concen","authors_text":"M.M. Hedman","cross_cats":["astro-ph.IM"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.EP","submitted_at":"2019-04-16T14:36:18Z","title":"Using Cosmogenic Lithium, Beryllium and Boron to Determine the Surface Ages of Icy Objects in the Outer Solar System"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1904.07727","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:dade612ff9704620acb30d634d201e1c056c10195d4fbd5555862fd598933978","target":"record","created_at":"2026-05-17T23:46:52Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"5eb13a8835e91bb0000d25e28fcbd817e9904eeea383ea2e4f8bf39204f5df82","cross_cats_sorted":["astro-ph.IM"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.EP","submitted_at":"2019-04-16T14:36:18Z","title_canon_sha256":"9453fc6d3da006821bbe67ff4361497b7ae7b61efb61e51dc2afe0e069e11835"},"schema_version":"1.0","source":{"id":"1904.07727","kind":"arxiv","version":1}},"canonical_sha256":"136ebb83c11bf28f86c8cde6456cc03dc3d558f12a6132e80ea28ad792ee50d4","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"136ebb83c11bf28f86c8cde6456cc03dc3d558f12a6132e80ea28ad792ee50d4","first_computed_at":"2026-05-17T23:46:52.422678Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:46:52.422678Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"x0KmtfFHxzx3HhYAXOQ3hGduI27ksx/yi3P20zO+1zEHcRZ909s94LOWlh1DFYyn9Au+XAtMBp7o3DFRMI6sAw==","signature_status":"signed_v1","signed_at":"2026-05-17T23:46:52.423169Z","signed_message":"canonical_sha256_bytes"},"source_id":"1904.07727","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:dade612ff9704620acb30d634d201e1c056c10195d4fbd5555862fd598933978","sha256:76a1affd528f1fd55f9db2f0bf20fdf084bd4b0688ed98cab13111b843e3e279"],"state_sha256":"5010ba4526fc51e507df4f8a6bddf07371c2c037ea0847df348f46b3ee4bc8fb"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"SnWjQ90rr5n5CQ+Ei8/QmRNVC6MdYhY6S9SKbkTq1KoK7m8cIrfDIN4yf1IJqV1fA8exuyd4Fo1zq2sYSWawAw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-04T17:31:17.630849Z","bundle_sha256":"1429d63797abad434e3a8dc21e0446989ebd50e48075420da3f3c81f0274fd93"}}