A quasar is a supermassive black hole in the act of feeding, and it’s so bright that it drowns out the galaxy it sits in. That is a nuisance if you want to weigh the galaxy and weighing it is exactly what you need to do to understand how black holes and the host galaxies grew up together. There is a way round it however, catch a quasar whose galaxy happens to be bending the light of something further away, and the bending betrays the mass. The catch is that such alignments are vanishingly rare, and the survey that might contain them holds 800,000 quasars. A team at Ohio State set a neural network on the pile and it came back with seven.