Quake Catcher Network: SETI@home Spinoff Tracks Earth-Shakers

One of the youngest off-springs of SETI@home has been getting a great deal of attention recently. Known as the Quake-Catcher Network (QCN), this distributed computing project makes use of thousands of volunteers' computers to locate and track earthquakes. Since its launch earlier this year the network has already recorded two major shakers – one in April near Reno, Nevada, and one in July near Los Angeles.

Here's how it works: most modern laptops are equipped with a chip called an "accelerometer" that measures the computer's vibrations or sharp movements. This is designed to help protect the computer from sudden impacts, but QCN founders noticed that it could be used for a different purpose as well: recording ground movements. If thousands of computers all over the world were reporting their vibrations second by second, it would give researchers a global overview of seismic movements.

QCN is now turning this concept into reality: by downloading a simple program, any computer equipped with an accelerometer can become part of the quake-monitoring network. It then sends frequent reports on its shaking and vibrations to QCN headquarters at Stanford University, where the data is processed and ground movements registered.

Since accelerometers were not designed to measure Earthquakes, there are inevitably certain drawbacks to using them as seismometers. First and foremost is the fact that it doesn't take an earthquake to cause a laptop to shake. A truck passing nearby, a pet jumping on a desk, or even typing on the keyboard, are all motions that are recorded by the accelerometer and transmitted to QCN headquarters. The network needs some way to distinguish between these commonplace vibrations and an actual earthquake. This is why it is so important to have a large network of users: If a single computer is shaking, it may well be caused by a rambunctious pet. But if many computers in the same area all report violent shaking at the same time, then an Earthquake is almost certainly taking place.

With 1500 active volunteers and growing, the project is currently going through its testing stages. So far the network has managed to confirm known quakes, but the QCN team hopes that in the future it will be able to detect Earth movements in areas not covered by traditional seismometers. They even expect that thanks to the speed of the internet they may be able to provide early warning of an earthquake to regions not yet hit by approaching seismic waves.

The Quake Catcher Network is based at Stanford University and U.C. Riverside, and is led by Stanford's Carl Christensen and Jesse Lawrence and Riverside' Elizabeth Cochran. They are currently working on establishing a QCN desktop computer network to work alongside the laptop network. Desktops have the advantage of being heavier, steadier, and in close contact with the ground. A shaking desktop is therefore a far better indication of an Earth-shake than a vibrating laptop. Unfortunately desktop computers do not come with a built in accelerometer, and volunteers will have to plug an inexpensive chip into a USB port on their desktops if they wish to participate.

The QCN network is part of the BOINC family – the Berkeley Online Infrastructure for Network Computing. Spawned by the success of SETI home, BOINC offers an easy way for researchers to take advantage of the enormous resources of network computing. QCN is the latest of dozens of different projects using the BOINC backbone, in fields ranging from cancer research to molecular biology, particle physics to paleontology. As the founding sponsor of SETI@home, The Planetary Society takes pride that its original investment in SETI@home has proven so scientifically fruitful. It proves once more that a farsighted investment in the exploration of other worlds can have immediate benefits on our own world as well.