Astronomy Now Home

Citizen scientists
make pulsar discovery

Posted: 13 August 2010

Bookmark and Share

The citizen science project Einstein@home has made its first discovery thanks to the computing power volunteered by three members of the public: an unusual lone pulsar spinning 41 times per second.

Einstein@home uses the BOINC (Berkeley Open Infrastructure for Network Computing) software to allow 250,000 users in 192 countries to use the spare processing power of their home computer to help search for gravitational waves and pulsars. The pulsar data comes from a search for these spinning neutron stars conducted by the Arecibo radio observatory in Puerto Rico. The data from this survey is sent to Cornell University and the Albert Einstein Institute at the Max Planck Institute for Gravitational Physics in Germany. From here the raw data is pre-processed into packages that can be downloaded by the BOINC software, and is transmitted to volunteers, including Chris and Helen Colvin from Iowa, USA, and Daniel Gebhardt of Universitat Mainz in Germany. As the Einstein@home software ran in the background on their computers, it turned up evidence for a pulsar 17,000 light years away, since named PSR J2007+2722.

Members of the public using Einstein@home have discovered a new pulsar, like the one in this artistŐs impression. Image: NASA.

When a massive star explodes in a supernova, it leaves behind its crushed core in the form of a neutron star. These neutron stars are born spinning, and emit beams of radio waves along their rotational axes, so they appear to flash, or pulse, like a lighthouse. In the case of PSR J2007+2722 it is flashing at us 41 times per second. But it also has an unusually low magnetic field, which makes scientists think that it was once part of a binary system, but was disrupted when its companion star also exploded, and the force of the explosion kicked the pulsar out of the system.

“We think there should be more of these disrupted binary pulsars, but there haven’t been that many found,” says Professor Jim Cordes of Cornell University. Perhaps Einstein@home is the tool for discovering them?

Einstein@home is not the only volunteer science project running on the BOINC software. SETI@home, which searches radio data primarily from Arecibo for signals from extraterrestrial intelligences, was the first such project when it arrived on the scene in May 1999. SETI@home, and the BOINC software, was developed by scientists working at the University of California, Berkeley. Today, SETI@home forms the largest overall computation in history (recognised by the Guinness Book of Records); by September 2001 it had performed 1021 flops (Floating Point Operations per Second, which is a measure of a computer’s performance, see and by November 2009 had the ability to compute 769 teraFLOPS. This is because by linking the computers of 5.2 million volunteers, SETI@home is able to utilise computing power greater than the largest single supercomputer in the world. In essence, SETI@home is the world’s largest supercomputer.

The success of SETI@home has encouraged over 30 more science projects using the BOINC software, which besides astronomy also cover subjects ranging from researching cures for diseases, mathematical problems, software testing, quantum computing, cryptography, chemistry, molecular simulations of proteins, epidemiology, climate change, the study of botanical ecosystems, and results from the Large Hadron Collider. Astronomy-specific projects include Milkyway@home, Cosmology@home and Orbit@home, besides the aforementioned Einstein@home and SETI@home.

The BOINC software can be downloaded freely here and can be used by anyone with a computer connected to the Internet. It is simple to set up, and if you (or rather, your computer) discovers something, be it pulsars, aliens or the Higgs boson, you will share the credit and, like the Colvins and Daniel Gebhardt, receive a commemorative plaque for vital contributions to science. If you’ve never tried it before, give it a go, and don’t forget about other online citizen science projects such as Galaxy Zoo, Solar Stormwatch and the new SETIQuest. For more about SETI@home and SETIQuest, read our article here.