Science: Volunteers Find Rare Pulsar in Arecibo Data
A massive computing project that pools the collective power of hundreds of thousands of computers owned by volunteers from 192 different countries to “mine” large data sets has discovered a rare, isolated pulsar with a very low magnetic field, researchers say. This international computing network is known as Einstein@Home and the pulsar it identified, called PSR J2007+2722, represents the volunteer project’s first deep-space discovery.
Benjamin Knispel from the Albert Einstein Institute in Potsdam, Germany, and colleagues from around the world report this discovery in the 12 August issue of Science Express, saying the Einstein@Home project was able to identify the 40.8 hertz pulsar from radio survey data taken in February 2007 at the Arecibo Observatory in Puerto Rico. However, “citizen scientists” Chris and Helen Colvin from Ames, Iowa, and Daniel Gebhardt of Universität Mainz, Musikinformatik, Germany, are also credited with the discovery since their personal computers actually processed the data.
Position of PSR J2007+2722 (red circle) in the constellation of Vulpecula in the evening sky in August; constellations art overlaid for illustrative purposes.
View a larger version of this image. | Image courtesy of B. Knispel, Albert Einstein Institute
Initial analyses suggest that PSR J2007+2722 was once part of a binary star system, but that it likely became a type of pulsar known as a disrupted recycled pulsar. Experts also suggest that the pulsar’s magnetic field and spin axes are very closely aligned, and that its “pulses” are remarkably long.
“The pulsar that was identified with Einstein@Home is one of the more fast-spinning ones, but it also has a pretty low magnetic field,” said Bruce Allen, leader of the Einstein@Home project, director of the Albert Einstein Institute, and professor of physics at the University of Wisconsin in Milwaukee.
The discovery of PSR J2007+2722 provides hope that such massive computing power provided by volunteers in the Einstein@Home and other such projects will lead to more findings in the future.
“The collective computing power of all of these computers around the world is substantially more powerful than the largest supercomputers,” said Allen. “This kind of volunteer computing takes advantage of the fact there are more than one billion computers around the world—at peoples’ homes and at work—and a lot of the time, they’re not really doing anything. They’re just sitting there idle. So, the point of Einstein@Home is to take advantage of all those idle computers.”
For five years the cooperative computing power of the Einstein@Home project has been poring over data from U.S. Laser Interferometer Gravitational-Wave Observatories, or LIGOs for short, looking for sources of gravitational waves in deep space. In March, 2009, the network of computers turned its attention to data from the Arecibo Observatory, which is the largest and most sensitive radio telescope in the world. Now, approximately one-third of the computing capacity behind Einstein@Home is used to search through Arecibo data.
However, according to the volunteers who donate some of their processing power to participate in the program, the Einstein@Home program is hardly a burden.
Einstein@Home volunteers Chris and Helen Colvin | Image courtesty of Chris Colvin
“I just use my personal computer at home—the same that I use for email and surfing the Web,” Chris Colvin said. His wife, Helen, added: “It’s a very nice screensaver. You get to see a rotating map of the stars. But other than that, there’s not much we have to do.”
Currently, the Einstein@Home project continues to analyze data collected from telescopes around the world, searching for gravitational wave signatures and other rare pulsars in deep space. In fact, Dr. Allen admits that the volunteer computing project has already made a second discovery.
“We’ve already found another binary system with Einstein@Home—but we’re not prepared to release that data yet,” he said.