{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:PBI5TMCBQ7CGL35WCNNVL4IDPQ","short_pith_number":"pith:PBI5TMCB","canonical_record":{"source":{"id":"1802.07640","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-21T16:12:50Z","cross_cats_sorted":[],"title_canon_sha256":"35cdc7a54df8359e57f5ae5077e9288f744c0499aa1e41cb08606bfe79e68578","abstract_canon_sha256":"ef07f8094eb68076464832d16e086e8e78f33a768e1875c25b9f5bb8759c2d75"},"schema_version":"1.0"},"canonical_sha256":"7851d9b04187c465efb6135b55f1037c3f4b5fee5fa99ddfaf55db02696761ed","source":{"kind":"arxiv","id":"1802.07640","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1802.07640","created_at":"2026-05-18T00:22:49Z"},{"alias_kind":"arxiv_version","alias_value":"1802.07640v2","created_at":"2026-05-18T00:22:49Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1802.07640","created_at":"2026-05-18T00:22:49Z"},{"alias_kind":"pith_short_12","alias_value":"PBI5TMCBQ7CG","created_at":"2026-05-18T12:32:43Z"},{"alias_kind":"pith_short_16","alias_value":"PBI5TMCBQ7CGL35W","created_at":"2026-05-18T12:32:43Z"},{"alias_kind":"pith_short_8","alias_value":"PBI5TMCB","created_at":"2026-05-18T12:32:43Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:PBI5TMCBQ7CGL35WCNNVL4IDPQ","target":"record","payload":{"canonical_record":{"source":{"id":"1802.07640","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-21T16:12:50Z","cross_cats_sorted":[],"title_canon_sha256":"35cdc7a54df8359e57f5ae5077e9288f744c0499aa1e41cb08606bfe79e68578","abstract_canon_sha256":"ef07f8094eb68076464832d16e086e8e78f33a768e1875c25b9f5bb8759c2d75"},"schema_version":"1.0"},"canonical_sha256":"7851d9b04187c465efb6135b55f1037c3f4b5fee5fa99ddfaf55db02696761ed","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:22:49.013530Z","signature_b64":"4qJ0gVuhPbSnrWl5lOqOopJJTpMUBXlFgiUNkQjaQvdPmDRrH+4k3EuO6SGtdbwvoF1bC6BPZAyYl10P72h7Bg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"7851d9b04187c465efb6135b55f1037c3f4b5fee5fa99ddfaf55db02696761ed","last_reissued_at":"2026-05-18T00:22:49.013086Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:22:49.013086Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1802.07640","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:22:49Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"cBjChDYV0S1xXspYLCwuLu7zcFbPdzKSz4U7n0Pzha1Zy7HX+gfymPzlFVJV5jxKFxjbbaYyYbE7e5qFffjqCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-22T21:22:28.739990Z"},"content_sha256":"0925d5b7f1569a182d54ff3361b8ea9a564664b8efdfbdd0a977fd56771ccc33","schema_version":"1.0","event_id":"sha256:0925d5b7f1569a182d54ff3361b8ea9a564664b8efdfbdd0a977fd56771ccc33"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:PBI5TMCBQ7CGL35WCNNVL4IDPQ","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Antenna Design and Implementation for the Future Space Ultra-Long Wavelength Radio Telescope","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"Amin Aminaei, Hamid Reza Pourshaghaghi, Heino Falcke, Leonid I. Gurvits, Linjie Chen, Marc Klein Wolt, Yihua Yan","submitted_at":"2018-02-21T16:12:50Z","abstract_excerpt":"In radio astronomy, the Ultra-Long Wavelengths (ULW) regime of longer than 10 m (frequencies below 30 MHz), remains the last virtually unexplored window of the celestial electromagnetic spectrum. The strength of the science case for extending radio astronomy into the ULW window is growing. However, the opaqueness of the Earth's ionosphere makes ULW observations by ground-based facilities practically impossible. Furthermore, the ULW spectrum is full of anthropogenic radio frequency interference (RFI). The only radical solution for both problems is in placing an ULW astronomy facility in space. "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1802.07640","kind":"arxiv","version":2},"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":"2026-05-18T00:22:49Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Oq0cTBSsR5zFC07+KpMVQLFEk4d/6ZTE7rfvs38gAxPGeFWVPJeAKqU6p/bZkYJYSBueMIBkbeX0QNKgKBaYBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-22T21:22:28.740677Z"},"content_sha256":"0dcc515f8042e3fc50970f86eaa7e393380d498847aac836c35d25e7150e7593","schema_version":"1.0","event_id":"sha256:0dcc515f8042e3fc50970f86eaa7e393380d498847aac836c35d25e7150e7593"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/PBI5TMCBQ7CGL35WCNNVL4IDPQ/bundle.json","state_url":"https://pith.science/pith/PBI5TMCBQ7CGL35WCNNVL4IDPQ/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/PBI5TMCBQ7CGL35WCNNVL4IDPQ/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":"2026-05-22T21:22:28Z","links":{"resolver":"https://pith.science/pith/PBI5TMCBQ7CGL35WCNNVL4IDPQ","bundle":"https://pith.science/pith/PBI5TMCBQ7CGL35WCNNVL4IDPQ/bundle.json","state":"https://pith.science/pith/PBI5TMCBQ7CGL35WCNNVL4IDPQ/state.json","well_known_bundle":"https://pith.science/.well-known/pith/PBI5TMCBQ7CGL35WCNNVL4IDPQ/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:PBI5TMCBQ7CGL35WCNNVL4IDPQ","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":"ef07f8094eb68076464832d16e086e8e78f33a768e1875c25b9f5bb8759c2d75","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-21T16:12:50Z","title_canon_sha256":"35cdc7a54df8359e57f5ae5077e9288f744c0499aa1e41cb08606bfe79e68578"},"schema_version":"1.0","source":{"id":"1802.07640","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1802.07640","created_at":"2026-05-18T00:22:49Z"},{"alias_kind":"arxiv_version","alias_value":"1802.07640v2","created_at":"2026-05-18T00:22:49Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1802.07640","created_at":"2026-05-18T00:22:49Z"},{"alias_kind":"pith_short_12","alias_value":"PBI5TMCBQ7CG","created_at":"2026-05-18T12:32:43Z"},{"alias_kind":"pith_short_16","alias_value":"PBI5TMCBQ7CGL35W","created_at":"2026-05-18T12:32:43Z"},{"alias_kind":"pith_short_8","alias_value":"PBI5TMCB","created_at":"2026-05-18T12:32:43Z"}],"graph_snapshots":[{"event_id":"sha256:0dcc515f8042e3fc50970f86eaa7e393380d498847aac836c35d25e7150e7593","target":"graph","created_at":"2026-05-18T00:22:49Z","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":"In radio astronomy, the Ultra-Long Wavelengths (ULW) regime of longer than 10 m (frequencies below 30 MHz), remains the last virtually unexplored window of the celestial electromagnetic spectrum. The strength of the science case for extending radio astronomy into the ULW window is growing. However, the opaqueness of the Earth's ionosphere makes ULW observations by ground-based facilities practically impossible. Furthermore, the ULW spectrum is full of anthropogenic radio frequency interference (RFI). The only radical solution for both problems is in placing an ULW astronomy facility in space. ","authors_text":"Amin Aminaei, Hamid Reza Pourshaghaghi, Heino Falcke, Leonid I. Gurvits, Linjie Chen, Marc Klein Wolt, Yihua Yan","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-21T16:12:50Z","title":"Antenna Design and Implementation for the Future Space Ultra-Long Wavelength Radio Telescope"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1802.07640","kind":"arxiv","version":2},"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":"sha256:0925d5b7f1569a182d54ff3361b8ea9a564664b8efdfbdd0a977fd56771ccc33","target":"record","created_at":"2026-05-18T00:22:49Z","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":"ef07f8094eb68076464832d16e086e8e78f33a768e1875c25b9f5bb8759c2d75","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-21T16:12:50Z","title_canon_sha256":"35cdc7a54df8359e57f5ae5077e9288f744c0499aa1e41cb08606bfe79e68578"},"schema_version":"1.0","source":{"id":"1802.07640","kind":"arxiv","version":2}},"canonical_sha256":"7851d9b04187c465efb6135b55f1037c3f4b5fee5fa99ddfaf55db02696761ed","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"7851d9b04187c465efb6135b55f1037c3f4b5fee5fa99ddfaf55db02696761ed","first_computed_at":"2026-05-18T00:22:49.013086Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:22:49.013086Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"4qJ0gVuhPbSnrWl5lOqOopJJTpMUBXlFgiUNkQjaQvdPmDRrH+4k3EuO6SGtdbwvoF1bC6BPZAyYl10P72h7Bg==","signature_status":"signed_v1","signed_at":"2026-05-18T00:22:49.013530Z","signed_message":"canonical_sha256_bytes"},"source_id":"1802.07640","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:0925d5b7f1569a182d54ff3361b8ea9a564664b8efdfbdd0a977fd56771ccc33","sha256:0dcc515f8042e3fc50970f86eaa7e393380d498847aac836c35d25e7150e7593"],"state_sha256":"310f1ff08c74dc1bc0bd6ff6b36fe11254c0e8e3bd594096891edce624a8975b"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"bbiZfsqOUrYjU0BRuDV6OG+HtoiUgvLyA93B/9SkFe3AirvB94VSRdkYNUo0VWPHhHcFsZO/3QA9x72BixaVCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-22T21:22:28.743988Z","bundle_sha256":"d40f6a31b8d51aaf984383dfdcfebdfd2373ba577fe78e856c11bd214217f984"}}