The genesis block and its headline

Wonder

1. Why does the first block carry a paraphrase of that morning’s newspaper headline?
2. How is the genesis output structurally excluded from the spendable database?
3. What explains the six-day gap between the genesis timestamp and the announcement of v0.1?

Explore

1. Block zero was mined on January 3, 2009. Its coinbase input contains the text ‘The Times 03/Jan/2009 Chancellor on brink of second bailout for banks’, a paraphrase of that day’s front-page headline about Chancellor Alistair Darling. The message serves two functions: it timestamps the block to a specific edition of the British newspaper, proving the earliest possible creation date, and it references the UK bank bailout occurring simultaneously. It is widely read as a comment on the banking crisis the system was built to stand apart from.
2. The genesis block includes a 50 BTC reward in its coinbase transaction. However, this output is not added to the Unspent Transaction Output (UTXO) set. Because it does not enter the database of spendable coins, these 50 BTC are permanently inaccessible and unspendable by any party, including the creator. Whether this was deliberate or a quirk of the original code has never been confirmed.
3. Satoshi Nakamoto announced Bitcoin v0.1 on the cryptography mailing list between January 8 and 9, 2009. Block 1 is timestamped January 9, 2009. The interval between the genesis block date (January 3) and this announcement represents a gap of roughly six days that has never been publicly explained or documented in the software’s early history.
4. The genesis block header is hard-coded into every instance of Bitcoin Core software. It is not mined by nodes upon joining; it is pre-loaded as the root of the chain. Every subsequent block links to its predecessor via a hash, meaning any current block can be traced backward through its parent hashes until it reaches this specific origin point.
5. The coinbase input’s script field accepts arbitrary data between 2 and 100 bytes. In the genesis block, this field holds the ASCII string of the newspaper headline. While modern miners use this space for extra nonces or pool identification strings, the genesis block used it for a message.
6. Open a block explorer and navigate to block height zero. Read the coinbase text in its raw hex and ASCII representations to verify the exact character encoding of the headline. Note that while tribute payments have been sent to the address associated with the genesis key, these payments do not activate the original unspendable output; they are separate transactions directed to a known public key.

Key facts

Exercise nine, six, three, one

Fact check

Dates, figures and claims checked against the published sources listed below.

• S. Nakamoto, 'Bitcoin: A Peer-to-Peer Electronic Cash System' (2008)
• Bitcoin Core source code, chainparams.cpp
• The Times, front page (January 3, 2009)
• S. Nakamoto, 'Bitcoin v0.1 released', cryptography mailing list (January 2009)