The Galactic Census

Two weeks ago, astronomers announced Galaxy Zoo, a website created as an interface to the largest galactic census ever compiled, encompassing some 1 million galaxies.

Computer programs have thus far been less-than-accurate classifying the myriad of galactic bodies photographed by the Apache Point Observatory near Sunspot, new Mexico. It takes creative human minds trained to recognize relevant patterns to accurately classify this wealth of data. Astronomers expect that with 10,000 to 20,000 people participating on the website, the process could take as little as a month, drastically shortening a task that could otherwise drag on for years. "We're in the golden era of astronomy. We have more data than we can assimilate and we need help," says University of Portsmouth astronomer Bob Nichol.

After registering on the website, a brief tutorial tests the participants' skills at classifying images. From there it's basically a game, clicking through the images and classifying the galaxies as spiral, elliptical or unknown. The data will help astronomers better understand galaxy interaction and formation.

This online collective sampling is not entirely new. In 2006, NASA enlisted volunteers to wade through images of space dust gathered from the Stardust spacecraft, which intercepted Comet Wild 2 and returned to Earth with particle samples from its trail. Amazon.com's Mechanical Turk also enlists the wisdom of the crowds, offering a number of pattern recognition tasks in exchange for small payments.