It’s a Zoo Out There: Galaxy Project Engages ‘Armchair Scientists’

Posted: November 24, 2009 at 8:01 am, Last Updated: November 24, 2009 at 8:41 am

By Tara Laskowski

It’s no secret we live in a world of information overload. With satellite images producing more information in one day than a person could analyze in several months, and millions of galaxies and other objects in space waiting to be classified and categorized, scientists are struggling to find new, transformative ways of doing their jobs.

Enter citizen scientists.

<p>John Wallin</p>

John Wallin

John Wallin, associate professor of computational and data sciences, is one of many researchers attempting to engage the general public in scientific puzzles. He is currently working on a project called Galaxy Zoo: Mergers.

The Mergers web site is a spin-off of an earlier project called Galaxy Zoo, a web site that allows anyone — scientist or not — to log in and help categorize the more than one million galaxies of our universe into different classifications with a few clicks of the keyboard.

Now Mergers, which launches on Nov. 24, is going even further by allowing these citizen or “armchair” scientists to do computer modeling of galaxies to determine how collisions happen.

These people — more than 250,000 different users now — are helping Wallin and his partners at the University of Oxford and Adler Planetarium do “what computers are really bad at,” says Wallin.

The hard-core users of Galaxy Zoo have discovered things that a machine would not have found, and Wallin hopes that eventually, Mergers users will as well. In fact, Galaxy Zoo users have discovered an entirely new classification of galaxy they called “green peas” — densely packed clusters of millions of stars, which, in pictures, look like little greenish balls. Others noted oddities such as illuminated gas clouds that were in need of further investigation.

All of the classifications and models done by users of the Zoo sites are tracked in a large database. To ensure minimal errors, users are weighted based on their accuracy and calibrated against an expert sample. Training sessions are also available on the web site.

A screen shot of the Galaxy Zoo web site.

A screen shot of the Galaxy Zoo web site.

When Galaxy Zoo was first launched in 2007, the team that developed the original project thought that it would take about two years for people to log in and, in masses, help categorize all of the million-plus galaxies.

However, after some press coverage of the site, more than 70,000 galaxies were being classified every hour, more than the amount one graduate student could do working full-time for an entire week.

“It’s really incredible,” says Wallin. “That’s when we knew we were onto something special here — that this was an educational tool as well as a scientific one.”

Already, 16 papers have been submitted to scientific journals based on Galaxy Zoo data, and educational studies have cropped up trying to determine the motivation behind the people who use the site. Some of them, Wallin says, are applying to graduate school for science because they are so excited from participating in this project.

“These volunteers who participate are not just users,” says Chris Lintott of Oxford University, the project lead for the Galaxy Zoo project.

“They’re doing science. They’re doing the analysis we don’t have time for, because there’s not enough professional scientists to do the job.”

Merger Zoo is just one piece of a larger project that will be funded by a National Science Foundation grant whose overarching goal is using innovative ways to deal with the sheer mass of data that science produces.

Other projects the grant will fund include transcribing millions of ancient Greek papyri uncovered more than 100 years ago by British archaeologists. In the past 100 years, only a small percentage of these papyri have been transcribed. By allowing the public access to transcribe one Greek letter at a time, researchers hope to translate these scribes much more quickly.

The ultimate goal of all these projects for Wallin is to use the data from the citizen scientists to train computers to become better at looking at things in a scientific way.

“It’s a partnership between what humans can do and what machines can do,” he says.

This idea of using the general public for scientific data gathering is not new, Wallin says.

NASA, for example, has a project called Clickworkers that lets people help measure and count craters on Mars, and The Audubon Society uses bird watchers across the country to help gather data on bird populations.

“The way our project is different is that instead of allowing the public to gather data, we take the professional data and bring it to the public to analyze. This is a new mode of interaction for volunteers to help out science because they are making meaningful contributions to science. They aren’t just reading about it, they’re doing it.”

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