{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2020:7P42MXQK2CDHWBVPR3442B5LPA","short_pith_number":"pith:7P42MXQK","canonical_record":{"source":{"id":"2012.04042","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-07T20:33:56Z","cross_cats_sorted":[],"title_canon_sha256":"4c66566ec068148cbb90e1135d7dba8887d54c4f26720d62568f73000aaf7ef9","abstract_canon_sha256":"de8bd63edfd830fe5ed92ced2c028635ec414915964d82ea497dc0d4ad2df0f9"},"schema_version":"1.0"},"canonical_sha256":"fbf9a65e0ad0867b06af8ef9cd07ab782ecb6e79098cec4f379c2d2e81c2f055","source":{"kind":"arxiv","id":"2012.04042","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2012.04042","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"arxiv_version","alias_value":"2012.04042v1","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2012.04042","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"pith_short_12","alias_value":"7P42MXQK2CDH","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"pith_short_16","alias_value":"7P42MXQK2CDHWBVP","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"pith_short_8","alias_value":"7P42MXQK","created_at":"2026-07-05T02:13:56Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2020:7P42MXQK2CDHWBVPR3442B5LPA","target":"record","payload":{"canonical_record":{"source":{"id":"2012.04042","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-07T20:33:56Z","cross_cats_sorted":[],"title_canon_sha256":"4c66566ec068148cbb90e1135d7dba8887d54c4f26720d62568f73000aaf7ef9","abstract_canon_sha256":"de8bd63edfd830fe5ed92ced2c028635ec414915964d82ea497dc0d4ad2df0f9"},"schema_version":"1.0"},"canonical_sha256":"fbf9a65e0ad0867b06af8ef9cd07ab782ecb6e79098cec4f379c2d2e81c2f055","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T02:13:56.835256Z","signature_b64":"fOH0FFjjKmN39b7v+cZDdTNxboEQCZyBlIG3g5CO31/ZuCgbHZ22OvvW/s/V8qC+U2gm4icRNdO7oWEh4oSCCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"fbf9a65e0ad0867b06af8ef9cd07ab782ecb6e79098cec4f379c2d2e81c2f055","last_reissued_at":"2026-07-05T02:13:56.834602Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T02:13:56.834602Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2012.04042","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":"2026-07-05T02:13:56Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"L6K+vQC97P1jpIhVR7w8OjsbkkFwX3MVdrVC+KOis/fXVQ8dU48f958EGJDplinPWWRB0LWbbuTfdOpbPHJeDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-20T20:28:39.571445Z"},"content_sha256":"d0b5728ce6812cd446c32c79365a0344252fb7ffa08eadb8b4b59cba28fe7dcf","schema_version":"1.0","event_id":"sha256:d0b5728ce6812cd446c32c79365a0344252fb7ffa08eadb8b4b59cba28fe7dcf"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2020:7P42MXQK2CDHWBVPR3442B5LPA","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Correcting Sky Quality Meter measurements for aging effects using twilight as calibrator","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"Axel Schwope, Johannes Puschnig, Magnus N\\\"aslund, Stefan Wallner","submitted_at":"2020-12-07T20:33:56Z","abstract_excerpt":"In the last decade numerous Sky Quality Meters (SQMs) were installed throughout the globe, aiming to assess the temporal change of the night sky brightness (NSB), and thus the change in light pollution. However, it has become clear that SQM readings may be affected by aging effects such as degradation of the sensor sensitivity and/or loss of transmissivity of optical components (filter, housing window). To date, the magnitude of the darkening has not been assessed in a systematic way. We report for the first time on the quantification of the SQM aging effect and describe the applied method. We"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2012.04042","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2012.04042/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2026-07-05T02:13:56Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"8HL2wItX8E4IcK8rYDe/abT+E36kahf9D4k66RF5qddTt3syu76c9k5tjrjy4GZIl1qzlRQk5CTV37Kop4EdBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-20T20:28:39.571827Z"},"content_sha256":"43ab1d0be4649d2764135ad32935754cdf7a0e95e6c178d3e77b891f5c29f3ea","schema_version":"1.0","event_id":"sha256:43ab1d0be4649d2764135ad32935754cdf7a0e95e6c178d3e77b891f5c29f3ea"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/7P42MXQK2CDHWBVPR3442B5LPA/bundle.json","state_url":"https://pith.science/pith/7P42MXQK2CDHWBVPR3442B5LPA/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/7P42MXQK2CDHWBVPR3442B5LPA/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":"2026-07-20T20:28:39Z","links":{"resolver":"https://pith.science/pith/7P42MXQK2CDHWBVPR3442B5LPA","bundle":"https://pith.science/pith/7P42MXQK2CDHWBVPR3442B5LPA/bundle.json","state":"https://pith.science/pith/7P42MXQK2CDHWBVPR3442B5LPA/state.json","well_known_bundle":"https://pith.science/.well-known/pith/7P42MXQK2CDHWBVPR3442B5LPA/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2020:7P42MXQK2CDHWBVPR3442B5LPA","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":"de8bd63edfd830fe5ed92ced2c028635ec414915964d82ea497dc0d4ad2df0f9","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-07T20:33:56Z","title_canon_sha256":"4c66566ec068148cbb90e1135d7dba8887d54c4f26720d62568f73000aaf7ef9"},"schema_version":"1.0","source":{"id":"2012.04042","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2012.04042","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"arxiv_version","alias_value":"2012.04042v1","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2012.04042","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"pith_short_12","alias_value":"7P42MXQK2CDH","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"pith_short_16","alias_value":"7P42MXQK2CDHWBVP","created_at":"2026-07-05T02:13:56Z"},{"alias_kind":"pith_short_8","alias_value":"7P42MXQK","created_at":"2026-07-05T02:13:56Z"}],"graph_snapshots":[{"event_id":"sha256:43ab1d0be4649d2764135ad32935754cdf7a0e95e6c178d3e77b891f5c29f3ea","target":"graph","created_at":"2026-07-05T02:13:56Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2012.04042/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"In the last decade numerous Sky Quality Meters (SQMs) were installed throughout the globe, aiming to assess the temporal change of the night sky brightness (NSB), and thus the change in light pollution. However, it has become clear that SQM readings may be affected by aging effects such as degradation of the sensor sensitivity and/or loss of transmissivity of optical components (filter, housing window). To date, the magnitude of the darkening has not been assessed in a systematic way. We report for the first time on the quantification of the SQM aging effect and describe the applied method. We","authors_text":"Axel Schwope, Johannes Puschnig, Magnus N\\\"aslund, Stefan Wallner","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-07T20:33:56Z","title":"Correcting Sky Quality Meter measurements for aging effects using twilight as calibrator"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2012.04042","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:d0b5728ce6812cd446c32c79365a0344252fb7ffa08eadb8b4b59cba28fe7dcf","target":"record","created_at":"2026-07-05T02:13:56Z","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":"de8bd63edfd830fe5ed92ced2c028635ec414915964d82ea497dc0d4ad2df0f9","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-07T20:33:56Z","title_canon_sha256":"4c66566ec068148cbb90e1135d7dba8887d54c4f26720d62568f73000aaf7ef9"},"schema_version":"1.0","source":{"id":"2012.04042","kind":"arxiv","version":1}},"canonical_sha256":"fbf9a65e0ad0867b06af8ef9cd07ab782ecb6e79098cec4f379c2d2e81c2f055","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"fbf9a65e0ad0867b06af8ef9cd07ab782ecb6e79098cec4f379c2d2e81c2f055","first_computed_at":"2026-07-05T02:13:56.834602Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T02:13:56.834602Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"fOH0FFjjKmN39b7v+cZDdTNxboEQCZyBlIG3g5CO31/ZuCgbHZ22OvvW/s/V8qC+U2gm4icRNdO7oWEh4oSCCA==","signature_status":"signed_v1","signed_at":"2026-07-05T02:13:56.835256Z","signed_message":"canonical_sha256_bytes"},"source_id":"2012.04042","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:d0b5728ce6812cd446c32c79365a0344252fb7ffa08eadb8b4b59cba28fe7dcf","sha256:43ab1d0be4649d2764135ad32935754cdf7a0e95e6c178d3e77b891f5c29f3ea"],"state_sha256":"9090c24a2b45dfbeca39484d1b20a2a5dd0fa866b027b305b43c654f8e003d2b"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"nb22Ialkw+dUrFNNxLenq7WgrMQfW7q9miI9sxxFg1S8/MObOLMpcbmTbOqWeca5/Q15MP0QRtqevgK8QX0qCw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-20T20:28:39.574373Z","bundle_sha256":"73ad4ddcfc44c68b68e5ec7b1b6f0be0822b96fb696659d6fae7c1c0ab565f68"}}