Black 2009
The last sat of each block mined in 2009 (heights 0 to 32,489), black rares excepted: 32,474 black sats, shown on the site as Black with ?year=2009.
How a sat qualifies
A Black 2009 sat is a black sat with a height scope: blocks 0 to 32,489, the blocks mined in 2009. A black sat is the last sat of a block's subsidy; every block of 2009 paid 50 BTC, so the last sat of block h is sat h × 5,000,000,000 + 4,999,999,999, from 4,999,999,999 (block 0) to 162,449,999,999,999 (block 32,489).
Black tiers are exclusive: a last sat that ends a difficulty adjustment period, when h + 1 is a multiple of 2,016, is black rare and not black. Sixteen blocks of 2009 end one (2,015, 4,031 … 32,255), so of 32,490 blocks, 32,474 end on a black sat.
Each is also an omega, the last sat of a bitcoin. They include the vintage blacks of blocks 0 to 999 and the Nakamoto blacks, which are all from 2009.
Why collectors care
It is the black sat of Bitcoin's first year: one per block, closed since the last block of 2009.
On this site
Black 2009 used to be a collection of its own. It is now Black in 2009: the Black collection narrowed to the year, with the same supply, holders, sales and listings. Old links to the Black 2009 collection redirect there. The year filter works the same way on any other collection: see 2009 sats.
How many
32,474 will ever exist, all mined: fixed rule arithmetic, as above. Black in 2009 shows how many are extracted and who holds them.