The nine year anniversary of the Bitcoin whitepaper being published reminded me of all the time I spent looking at the earliest portions of Bitcoin history back when I was in high school. The community has expanded a lot since then and so have my own skills so I figured I would go back and look at an early event that made history: that first payment of 10 BTC between Satoshi Nakamoto and Hal Finney.
The nature of the blockchain is that everyone can go and verify that this 10 BTC transaction actually took place. You can see it for yourself, right now, if you want.
Here it is! You can see the date on it, 2009-01-12. The bitcoin network was merely a few days old at this point.
The 50 BTC this transactions spends is from coins mined to the address 12cbQLTFMXRnSzktFkuoG3eHoMeFtpTu3S. Now look at the recipients of the transaction: First is 1Q2TWHE3GMdB6BZKafqwxXtWAWgFt5Jvm3, which Hal Finney has said was an address of his. And then 12cbQLTFMXRnSzktFkuoG3eHoMeFtpTu3S again, which is Satoshi Nakamoto sending 40 BTC back to himself as change. If you look at the other payments in 12cbQLTFMXRnSzktFkuoG3eHoMeFtpTu3S's history, you'll see that Satoshi actually sent coins to quite a few people, probably from the cryptography mailing list, although Hal Finney (the first recipient) is the only one of them that has ever been identified.
Hal told Satoshi that he would send those 10 bitcoins back, but he had forgotten to do that before Satoshi disappeared. Hal was later diagnosed with ALS, and sold his bitcoins in mid 2013 to pay the medical bills. He passed away, proud of his influential involvement in bitcoin and cryptography in general, in 2014.
That's all pretty interesting. But, hold on, why did Satoshi choose to spend the bitcoins from block #9 in particular? Why not block 1, or block 100, or something? 9 seems sort of arbitrary. None of the other bitcoins that were confirmed at that point were ever spent.
I couldn't figure out the answer when I was young. But I think that I've found out now. The first version of the bitcoin wallet chose which coins were to be spent in a transaction based on the transaction ID the coins came from (actually by how many there are first, but in this case, all the transactions mined precisely 50 BTC, so that doesn't make a difference). The first payment to Hal Finney was in block 170, and newly mined bitcoins can only be spent after they have 101 confirmations, so only coins up to block 68 were spendable when the first payment happened. (Block 0 doesn't count, because the bitcoins it created are unspendable.)
I grabbed the transaction IDs for all the bitcoins mined from blocks 1 to 68 and sorted them. Sure enough, the coins from block 9 are right on top:
0437cd7f8525ceed2324359c2d0ba26006d92d856a9c20fa0241106ee5a597c9 Block #9
04391286b3aefbb5df4cdb515ac7fce7942525fa602e1d7757e90a4fd41a1e20 Block #40
0731f33cf07a2e5f749a2910c437a015968e1fc2ed79c95634829167db280c4f Block #63
0e3e2357e806b6cdb1f70b54c3a3a17b6714ee1f0e68bebb44a74b1efd512098 Block #1
1484c18ba443b13851098597d8cb6d49d5983eab63c53d6b0dcc565612e7ca6b Block #39
194c9715279d8626bc66f2b6552f2ae67b3df3a00b88553245b12bffffad5b59 Block #49
19521c62482ac299b37c8ae4eab67abd150e3c21dc66b7e2b0919444769ee2ed Block #55
20251a76e64e920e58291a30d4b212939aae976baca40e70818ceaa596fb9d37 Block #6
223b0620a8f1c1f23a2ebf8032ed11321b921017d01974e74cddd651319b5474 Block #34
230cf03a6ce420eaa42e3c64feebb47920f3470efb4323b4574b4b6e5a004f65 Block #27
27c4d937dca276fb2b61e579902e8a876fd5b5abc17590410ced02d5a9f8e483 Block #42
2b9905f06583c01454f10f720b5709e3b667c9dd3d9efc423c97b7e70afdc0c9 Block #32
2f5c03ce19e9a855ac93087a1b68fe6592bcf4bd7cbb9c1ef264d886a785894e Block #43
32edede0b7d0c37340a665de057f418df634452f6bb80dcb8a5ff0aeddf1158a Block #48
3b96bb7e197ef276b85131afd4a09c059cc368133a26ca04ebffb0ab4f75c8b8 Block #12*
3c0db11484606a63b04ef4b8adcd665655939d3932ab1ebe90d1dfc5f077ca95 Block #59
3c6f58905f06a9fe9b4313a88827c43dbfb0156fcc3b17bb311d51e8be6746f5 Block #53
439aee1e1aa6923ad61c1990459f88de1faa3e18b4ee125f99b94b82e1e0af5f Block #44
43c39b8b3728c6cb26fae0fc18803ca6cf43e15fde218e3dfbd54e633cf6753e Block #24
50748b7a193a0b23f1e9494b51131d2f954cc6cf4792bacc69d207d16002080d Block #15
540a7e54fd64478554519f1b2d643ecc888c5030631487f9cfc530b71d281309 Block #50
63522845d294ee9b0188ae5cac91bf389a0c3723f084ca1025e7d9cdfe481ce1 Block #5
67c1e8143bb6ad221a4ce77d6c8be68f2e25e0743f51b2db1a7b22bab59014dc Block #26
6d344eb5d67ed329a1c1d7603bba4b85d5916435b49f7a585bb370b76820287d Block #37
701ce76c033e0b03fa79503770a5874840373e30cd9c1eca472ec66617f3a3ee Block #62
82a1e1731a9b22fdea55c09f2fac191a89efee127956fcfef65caab70f54002d Block #60
852b1997ed935ba638078998e2d15bc8a91b8ad232e2d988e22c969eba3bafe0 Block #35
86b33edba8ff663b0f73ef487e4433f34d26ef91de15659d2cc09594d27b52cb Block #31
8aa673bc752f2851fd645d6a0a92917e967083007d9c1684f9423b100540673f Block #7
9635054e3de101ea39dcfa5f4cec63ceb1205db6e0a99304c8db2b3a162137e4 Block #58
9962d5c704ec27243364cbe9d384808feeac1c15c35ac790dffd1e929829b271 Block #13
999e1c837c76a1b7fbb7e57baf87b309960f5ffefbf2a9b95dd890602272f644 Block #3
9b0f52332d7d013b49016416c4818b5abb80b01ca526b7b813830348ad2321be Block #25
9b0fc92260312ce44e74ef369f5c66bbb85848f2eddd5a7a1cde251e54ccfdd5 Block #2
9b9e461221e5284f3bfe5656efdc8c7cc633b2f1beef54a86316bf2ae3a3e230 Block #19
9e2eaf1d7e5178a2d116f331c340f1f7fd6de7540783ac36a7054fe9a4d64943 Block #22
9efa6cb3b8cca3c9387144f397f80e7b4bc2dd86026fdd308625a2e100a08d5a Block #41
a09c89d2a31440658a42ec97aeee0d36b01529e45b315922e2aa2955334d1821 Block #51
a3e0b7558e67f5cadd4a3166912cbf6f930044124358ef3a9afd885ac391625d Block #17
a6f7f1c0dad0f2eb6b13c4f33de664b1b0e9f22efad5994a6d5b6086d85e85e3 Block #8
ae6eedf8e47ac6dda10ca9f3334bd3031795c55a124948003acd944ebd31fee1 Block #61
b17fc28c1dc15ca4b05bf4784419c145b14e79ece54c793656997984c4e46715 Block #67
b3f978e6ee5e91662af30a634b3f3268c6f5d34aac1eb54e6cc9535026f5084f Block #52
bc0f0f8b3235421a036122299db7046a00c3a7cd1d650de3d92969780b873728 Block #57
bdc5121446fd203abbf0e4d13fe99594dc3dc4c1cb95504feb459e8982d923be Block #68
bdeaa0089cd84670da5e6385f0185c2d7978bf57a1aa5540d3ff3b3eabaa1210 Block #33
c361e2f4581f035dd58b99788347884e046e47b4c17ec347344ff8b24cd377ec Block #29
d05d256fbd5845b30039e37d48215788a4e438249048c47ddb9c83cd927d4d5a Block #36
d17b9c9c609309049dfb9005edd7011f02d7875ca7dab6effddf4648bb70eff6 Block #47
d3ad39fa52a89997ac7381c95eeffeaf40b66af7a57e9eba144be0a175a12b11 Block #10
d3dc9be5d58809579e56cdd64e78257ecd24e2726cf26ef0a698f4e5c07670b5 Block #54
ddd4d06365155ab4caaaee552fb3d8643207bd06efe14f920698a6dd4eb22ffa Block #46
df2b060fa2e5e9c8ed5eaf6a45c13753ec8c63282b2688322eba40cd98ea067a Block #4
e0175970efb4417950921bfcba2a3a1e88c007c21232ff706009cc70b89210b4 Block #21
e1afd89295b68bc5247fe0ca2885dd4b8818d7ce430faa615067d7bab8640156 Block #14
e1cf3476234d8446653ad52a8939ed792003eefdcd0e897319ab9d2cb4c14c8c Block #23
e690daeb9f73d29d8a22cb4b5ec29970e9b32283d4376adeaad8691ccb449a68 Block #38
e79fc1dad370e628614702f048edc8e98829cf8ea8f6615db19f992b1be92e44 Block #16
ebdb8335d5b148e9cc1b1bb795ee619a649bd1638e5514fdfc3004b1c56fd6a4 Block #64*
ee1afca2d1130676503a6db5d6a77075b2bf71382cfdf99231f89717b5257b5b Block #20
f01d7897ca02ed20dfb5544b3c1228e225fd97b72510d40af6c9d8e489033a74 Block #66
f15c7c51118c1dc93129a9f4999c7768ef2ff8cda3230f56d32576518c5f9349 Block #65
f399cb6c5bed7bb36d44f361c29dd5ecf12deba163470d8835b7ba0c4ed8aebd Block #28
f5e26c8b82401c585235c572ba8265f16f7d9304ed8e31c198eab571754f5331 Block #30
f69778085f1e78a1ea1cfcfe3b61ffb5c99870f5ae382e41ec43cf165d66a6d9 Block #45
f8325d8f7fa5d658ea143629288d0530d2710dc9193ddc067439de803c37066e Block #11
f925f26deb2dc4696be8782ab7ad9493d04721b28ee69a09d7dfca51b863ca23 Block #18
fe9ccc6c8b44c67ab170135d4148d6424e748f7549547d8174d59b5127df0102 Block #56
*nobody actually knows if Satoshi mined blocks 12 or 64, but they're here anyway to be sureHere's another fun fact. The 10 bitcoins Hal Finney got from the first payment weren't his first bitcoins. He actually mined block #78, so he already had 50 BTC that he had made himself before Satoshi sent him that payment. In 2014, Hal actually released a screenshot of his earliest transactions:
In this screenshot you can clearly see both the 50 he mined originally and the 10 he got from Satoshi. (He kept mining for a while after that!) Block 78 has another unsolved mystery, though. Its extraNonce parameter suggests that the person that mined block 78 also mined blocks 73 to 77, as you can see by the upward slope that they make when you plot blocks by extraNonce:
(The higher slope up there are blocks mined by Satoshi, and block 64 being way down there is the reason that we don't know if Satoshi mined it or not!)If we didn't know Hal mined block 78, and not blocks 73 to 77, we could infer from this chart a few things. First, Satoshi Nakamoto stopped mining after block 72, or restarted his miner, because the extraNonce slope ends there. Second, blocks 73 to 78 make a clear slope, highly suggestive that they were all found by the same person, be they Nakamoto or Finney, and in the same mining session. extraNonce can be wrong, and Hal claiming to have solved block 78 and not 73-77 suggests that it is. Is it just dumb luck that block 78 happened to look like it was on the same extraNonce slope as blocks 73-77? Why did Nakamoto stop mining right when Finney started? Additionally, there is a three hour gap between blocks 78 and 79. Why did Nakamoto wait for 3 hours after Finney stopped mining to start again? Was it just bad luck that it took so long to find a solution? These are unanswered questions. Feel free to speculate on what you think happened here!
Hopefully this was an interesting read, and happy bitcoin whitepaper anniversary!!!