According to God of Prompt on X, citing All day Astronomy, Harvard and Google generated 1.4 petabytes of data to map a 1 cubic millimeter fragment of human cortex—about one-millionth of the brain—using a $6 million electron microscope over 326 days of continuous imaging (as reported by All day Astronomy via X). According to the X thread, the dataset reveals roughly 150 million synapses per cubic millimeter, neurons with over 5,000 connections, coiled axons of unknown function, and mirror-image cell clusters that challenge current models (according to All day Astronomy via X). For AI, the business implication is clear: today’s billion-parameter neural networks remain far from the energy efficiency and wiring density of the human brain’s 20-watt operation, underscoring opportunities for neuromorphic hardware, sparse connectivity, and topology-aware training that better reflect biological constraints (as noted by All day Astronomy via X).