Ken Shirriff’s team programmed an Apollo Guidance Computer in 2019 to run Bitcoin’s double SHA-256 mining process, completing one hash in 10.3 seconds. The roughly 70-pound machine had about 4KB of RAM, 36K words of read-only memory and could perform about 40,000 additions per second. The team verified its code against already-mined block 286,819, but the computer never earned Bitcoin. At the 2019 network hashrate of about 65 EH/s, the AGC would have needed roughly one million times the age of the universe to find a block. Bitcoin’s hashrate reached 934 EH/s after the September 5, 2026 difficulty adjustment, which raised mining difficulty 1.31% to 127.45 trillion. At that hashrate, the machine would need roughly 13 million times the age of the universe to find a block. The comparison illustrates the scale of Bitcoin’s proof-of-work network, while recent hashprice and fee data show that the block subsidy remains the main source of miner revenue.