Earth & Sky was a daily radio series that presented information about science and nature. It began broadcasting in 1991 and ceased operations in 2013. EarthSky is the ongoing website, serving 21 mi
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7d57daadee888548b8b1b4253e8797bed0f228af7668a4562b61a9da66b6fda7. Chain 2 (Bitcoin): anchored in block 954693 (2026-06-21T11:50:32Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/e4dd441f-c76d-4c03-96b9-eec8f5fb4cc4.json and https://artists.proofprofile.net/proofs/artist/e4dd441f-c76d-4c03-96b9-eec8f5fb4cc4.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.