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This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute.

In 1930 astronomer¹ Clyde Tombaugh discovered the dwarf² planet Pluto³ while looking at photographs of the night sky. Pluto was the first object to be found in what's now known as the Kuiper Belt, a region that's also full of asteroids⁴. NASA's New Horizons spacecraft intends to visit one or two of them after it flies past Pluto in 2015. But which ones?

That's where you come in. Because astronomers⁵ are calling on citizen scientists to eyeball images that will help them find the outermost⁶ icy bodies in Pluto's neighborhood. The project is described at the Web site icehunters.org

Some of the largest telescopes on Earth have helped produce millions of images of the relevant region of space. By comparing photos taken at different times, scientists can subtract out objects that appear stationary⁷, like far-off galaxies⁸, and focus on things that appear to be moving in orbits, like asteroids.

Now, these pictures can be a bit messy. So scientists say they could use plenty of eyes to help scan the pics for things that move—the same way Tombaugh first found Pluto. The winning object could become the most distant ever visited by a spacecraft from Earth. But you don't even have to get off the couch.

Thanks for the minute. For Scientific American's 60-Second Science, I'm Karen Hopkin.