What happens when you ask the public to help learn more about the universe? Well, you might get more than 83,000 volunteer citizen scientists coming together to make over 16 million galaxy classifications on more than 300,000 nearby galaxies. In fact, that is exactly what happened with the project Galaxy Zoo 2, the second phase of a crowdsourcing effort to examine and classify nearby galaxies.
So why get the masses involved? Researchers acknowledge that computers are great at sifting through data and automatically measuring properties like the size and color of galaxies. But when it comes to characteristics like shape and structure, the current software isn’t up to speed. Human eyes are still better at picking out these details, and with so much data to go through, lots of eyes were needed.
From February 2009 through April 2010, the volunteers combed through online images gathered from the Sloan Digital Sky Survey. On average, each image was classified 40-45 times to ensure accuracy. As a result, an international team of researchers, led by the University of Minnesota, has produced a catalog based on this new galaxy data. The catalog is ten times larger than any previous catalog of its kind, and is available online. The researchers estimate that the combined efforts of the citizen scientists involved represents about 30 years of full-time work by one researcher.
"With today’s high-powered telescopes, we are gathering so many new images that astronomers just can’t keep up with detailed classifications," said Lucy Fortson, a professor of physics and astronomy in the University of Minnesota’s College of Science and Engineering and one of the co-authors of the research paper. "We could never have produced a data catalog like this without crowdsourcing help from the public."
The Galaxy Zoo 2 project focused on nearby galaxies, giving researchers a snapshot of galaxies as they are today. Next up, they will look at galaxies much farther away, to see how galaxies looked in the distant past. Comparing the results, astronomers will get a better understanding of how our universe is changing over time. Volunteers will continue to be needed, so if you want to participate, check out Galaxy Zoo for yourself.