So many galaxies and so little time! What can a busy scientist do? A team of international researchers solved that problem by turning to thousands of amateur volunteers around the world for help describing the universe. The result of that appeal is the “Galaxy List”.
Modern instruments allow us to peer deep into time and space, but on Earth it is still only 24 hours in a day. It’s a conundrum that researchers have faced more and more in recent years, as the volume of telescope images has outstripped attempts to organize them.
Now, an international group of scientists has decided to solve that problem by harnessing the power of the crowd and the Internet to help them deal with the vastness of space.
The result of that endeavor is ‘Galaxy Zoo’, a project dedicated to cataloging the heavens. Its second phase has just been completed.
Lucy Fortson, professor of physics and astronomy at the University of Minnesota in the USA and one of the project leaders explains:
“We find galaxies in two main morphologies or shapes: elliptical and spiral. The complexity of those shapes makes recognizing the differences very difficult for machine algorithms or computers. The best machine algorithm that can distinguish between these shapes, which is available to us, is the human brain. “An Oxford graduate (who worked on the project) and his supervisor were sitting in a pub and thought, ‘You know, if we put this on the Internet, are people going to classify galaxies?'” says Fortson.
The answer was a resounding yes. The first phase of the project, which ended in 2009, asked interested volunteers from around the world to help classify nearly a million galaxies from the near universe. A scientific background was not required. All that was needed were eyes, interest and the ability to register at galaxyzoo.org.
Fortsonova said that it was such a success that the participants asked the organizers to give them more tasks, which the scientists accepted. Now they’ve published their findings in “Galaxy Zoo 2,” a document containing some 16 million classifications made possible by over 83,000 enthusiasts.
The project featured 300,000 galaxies with the clearest images and asked volunteers not only to describe their basic shape, but also to provide a more detailed description: Does the galaxy contain spirals and how many spiral “arms” are present? Does the galaxy have “galactic bars” – long, elongated features that represent concentrations of stars? Is a galaxy merging with another galaxy?
The classifications were recorded between February 2009 and April 2010.
Scientists involved in the project say that the new catalog is ten times larger than any previous one. They estimate that it represents the result of thirty years of work by one researcher.
The data should help scientists answer questions that have long fascinated them.
“One of the biggest questions people are trying to figure out is how our universe evolved and how we got to where we are.” One aspect of this is understanding the formation of galaxies. We know that the personality of a galaxy is shaped by its history, and its history is written in the morphology of the galaxy,”
says Lucy Fortson.
Galaxy Zoo relies on responses from large groups, usually via the Internet, to come up with information or data, and is not the first scientific attempt to discover information about the universe.
For years, researchers into the existence of extraterrestrial life have used computer programs from several universities and research projects to scan the radio waves of space for signs of intelligence.
The rigor of science plays a role in projects based on collecting data from large groups of people. In the Galaxy Zoo 2 project, each galaxy was classified between 40 and 45 times to ensure data accuracy. Fortson said her team used “certain methods and formulas” to weed out the classifications of those participants who “weren’t really paying attention.”
The next step, she says, is to provide volunteers with a Hubble Telescope:
“I compared it with the census. We’ve just done an inventory of the present: We’ve gone round and interviewed all these galaxies and seen the diversity, the rich diversity of galaxies in our immediate universe. Now we want to go back in time and make a list of galaxies as they were formed.”
“By comparing the two censuses, we can learn how galaxies have evolved,”
concludes Fortson.
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