Wired Science

High School Science Teacher Reports From the Island of Maio

Some 300 miles off the West Coast of Senegal lies a very small, dusty island named Maio. It is here that Professor Michael Hedlin of the University of California at San Diego built an infrasound detector as part of a global network that will verify compliance of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). I tagged along as part of the ARMADA Project, a National Science Foundation-funded program that sends teachers throughout the world to witness and actively participate in field research. My job was to accompany Professor Hedlin’s crew and relay their experiences back to my students at West Salem High School in Oregon.

It took several days of plane travel to reach this Creole-speaking island of roughly 5,000 people, and the culture shock added to the scientific excitement of building an infrasound detector, which itself was intriguing enough. Among the unique characteristics of nuclear blasts is that they emit low-frequency sounds that can easily circle the world several times. By placing many of these detectors across the world you can pinpoint the location of a nuclear blast. The CTBT will network 60 of these detectors spanning the world, even as far away as Antarctica.

Isolated in the Atlantic Ocean, Maio is an ideal site for one of these detectors. It was selected because of its geographical location, the relative ease of installing the roughly two-kilometer-wide detector, and the presence of new Acacia trees as part of a reforestation project on the island -- the trees provide protection from the coastal winds that interfere with the infrasound signal.

Professor Hedlin worked for nearly three years planning the deployment of this detector, and carefully shipped all the needed equipment before the team’s arrival. For several months they connected miles of pipes in a geometrical array that funnels air into eight microbarometers. These instruments are so sensitive that they can easily detect air pressure fluctuations caused by waves crashing on the shore some 100 miles away. The barometers are linked to a central recording facility by radio, and all the data from across the world is monitored by scientists in their labs.

The project was in midstream when I arrived, and I spent the next several weeks connecting pipes, carrying equipment, building the solar panels and clearing brush. A full account of my experience can be found on the ARMADA website. It was enjoyable, hard work and provided me with a glimpse into the island culture. The people there are extremely kind and unhurried.

Ironically, while we were constructing the site, North Korea made the decision to detonate its first nuclear bomb. The site was not running yet, and it was a measure of the island’s remoteness that I did not know of the explosion until a few days later when a traveler told me what had happened.

On my return to my high school, several students took on the project of building their own infrasound detector and measured the difference between infrasound signals from the ocean surf and the interior valley. For a look into that project, read the teacher blog on this site.