The Citizen Zoo is celebrating a decade of distributed, citizen-driven astronomy, in which it has reordered scientists’ ideas of how science should be done. Long before the word “crowdsourcing” became fashionable, the project used volunteers from the world over to examine telescope images of distant galaxies. Apart from classifying galaxies and examining their development over aeons, these citizen scientists have identified new kinds of celestial objects and established that our own galaxy is not dormant, as it was canonically believed to be. The Milky Way is littered with thousands of objects which are up to something.
In recent years, the observations and knowledge of crowds are being harnessed in ways that would have seemed dangerous and heretical to earlier scientists and custodians of wisdom. The trailblazer was SETI@home, the Search for Extraterrestrial Intelligence’s distributed computing project, which harnesses the idle resources of home computers to listen for possible extraterrestrial radio signals from deep space. Every day, almost 3 lakh home computers connect to SETI at Berkeley to deliver computing power of 617 teraflops, which is faster than many defence supercomputers. However, SETI@home only taps into the computing resources of citizens. Using the liberal philosophy which has driven the support system of the open source movement, in which computer users responsibly help each other, Wikipedia uses volunteer editors to change the way in which knowledge is curated. By making the daring assumption that people are generally responsible, and by setting up a self-correcting mechanism for editorial control which is more reliable than was expected, it has created the world’s biggest encyclopaedia.
As we are groomed for a future when machines will apparently take over all human functions, from book-keeping to facial recognition, projects like Galaxy Zoo are good news. For years yet, perhaps, humans will continue to make sense of some kinds of data much faster than computers.