powers of four

For some Galaxy Zoo volunteers, the draw is somewhat more philosophical. Contemplating a galaxy that exists at an almost unimaginable distance, in both space and time, and contributing a bit of knowledge about it can be humbling and satisfying. "Every galaxy has a story to tell. They are beautiful, mysterious, and show how amazing our universe is," says Aida Berges, a homemaker in Puerto Rico who has classified 150,000 galaxies — at one point putting in 16-hour days. "It was love at first sight when I started in Galaxy Zoo ... It is a magical place, and it feels like coming home at last.