Through the Einstein@Home program, about 250,000 private citizens from 192 countries donate time on their home and office computers to help comb through astronomical data. Now, for the first time, three of those citizen scientists — Chris and Helen Colvin of Iowa and Daniel Gebhardt of Germany — have discovered a new radio pulsar in the constellation Vulpecula, located in the Milky Way Galaxy about 17,000 light years from Earth.

Pulsars are neutron stars that spin rapidly and emit a constant stream of electromagnetic particles ejected from the star’s magnetic poles at the speed of light. They were first discovered in 1967 as radio sources that blink on and off at a constant frequency. Pulsars with orbiting companions, called binary pulsars, played a key role in verifying Einstein’s theory of general relativity. But the pulsar detected by the Colvins and Gebhardt sits alone with no companion orbiting star, and astronomers believe it could be a recycled pulsar that lost its companion. This makes it particularly interesting to study, as the origin of recycled pulsars is still unknown.

The Einstein@Home project, based at the University of Wisconsin’s Center for Gravitation and Cosmology and the Max Planck Institute for Gravitational Physics, was started in 2005 to search for gravitational waves in data from the Laser Interferometer Gravitational-Wave Observatory (LIGO) at Caltech. In March 2009, the program expanded its search mission to look for signals from radio pulsars in data from Arecibo, the world’s largest and most sensitive radio telescope. Currently, about 500,000 volunteer computers help analyze data for Einstein@Home (an average of two computers per volunteer). The pulsar finding is the first genuine astronomical discovery by a public volunteer computing project.

Last week, a study of distributed computing applied to the problem of protein-folding found that computers are no replacement for human thinking and insight.

“No matter what else we find out about it, this pulsar is bound to be extremely interesting for understanding the basic physics of neutron stars and how they form,” said James M. Cordes, professor of astronomy at Cornell University.

A paper on the discovery was published today in Science Express.