Shaking up physics
"Sir," said a small boy to Stewart Bullen. "When there's an earthquake, do you feel happy or sad?" Looking up from a particularly fascinating print-out of seismographic data, Stewart knew the naive question went to the heart of his own science teaching: "This child was taking the science and expanding it into the world of emotional appreciation of a real global event".
The recent Asian tsunami has brought the human impact of earthquakes into almost everyone's minds. But what about their scientific significance? And can the two be combined?
Students at Hailey Hall School in Hertfordshire have no doubt that they can. "We could see from the waves that this earthquake was huge; a lot bigger than any other one," explains 11-year-old Josh, one of the newest seismography enthusiasts at the 60-pupil secondary school for boys with emotional and behavioural difficulties. "We're safe most of the time, but other countries have to put in defence systems," adds Duwane, aged 16.
"This is real science," says Stewart, who for the past six years has been squeezing as much geophysics as possible into the science curriculum at Hailey Hall. "With so much of the science we do in school, you mix A and B, observe this and that and conclude. There's no excitement, no surprise.
When you get an earthquake, youngsters immediately start asking questions about where it came from, how far away it is, why it happened. You can open up their minds."
So how does he do seismology in school? He started 10 years ago with a home-made seismometer, built from bits of aluminium, magnets and wire coils. This was at his previous school, Simon Balle Comprehensive in Hertford. "The coils of wire work like a microphone: the ground moves, the pendulum swings and it generates a current which can be amplified and modified."
The result is an electronically converted data record of earthquake ripples from faraway countries felt beneath our unsuspecting British feet.
A-level students find the seismometer and the seismic data "an Aladdin's cave of physics in action," Stewart says. "We talk about wave motion, about damping, about resonance, about fundamental physical principles."
The result was a surge in numbers of physics A-level students at Simon Balle and, an even more endangered species, entrants to university physics and Earth science courses.
Moving to Hailey Hall, he knew that the level of scientific understanding would be lower. However, the fascination was, if anything, greater, both for himself and for the pupils.
Students come into school in the morning and check the records to see if there has been an earthquake anywhere in the world overnight. They discover new places. Through understanding how earthquakes travel - primary (P) waves going faster than secondary (S) waves, but unable to penetrate the Earth so deeply - they come to understand the Earth's structure: its crust, mantle, moving plates and core. "There is an area called the P-wave shadow, where the waves won't go through the core," Stewart explains. "In school we can obtain observational evidence over time to support the theory that the Earth has a core, by showing that there are places where the P-waves won't go through. Seismology is like X-raying the Earth."
The basic tools for this X-ray are several software packages: WinQuest, which can be used to combine seismographic data from different sources and aid calculations of the origins, size and extent of an earthquake, and Seismic Waves, which simulates the movement of earthquakes across a global map, enabling students to read off fault lines and epicentres from superimposed circles showing how far each quake spreads. The software can also play back the movement of the earthquake from start to aftershocks.
Much of the data Hailey Hall students use is produced by American schools, which have their own seismic network, SpiNet, of which until very recently Hailey Hall was the only British member (Beale High School in Ilford has now joined them). Stewart is hoping not only to produce a package of seismographic software for schools to use, but also to establish a UK schools' network (email him for details).
Meanwhile, Hailey Hall has just been awarded a pound;1,000 Royal Society grant to improve its seismometer, possibly with a view to commercial production, and Stewart has been asked to join a Royal Astronomical Society committee advising on Earth science in the national curriculum. Even before the tsunami, he says, it was a subject whose time had come: "Astronomy has this tremendously high profile, but geophysics has just as much to offer in terms of science experience and in drawing youngsters to taking science seriously. It's relevant, it's observable, it's applicable and, most important, it's real.
"It's about being part of the global community at a hard, scientific level.
The children know our earthquake records are available on the internet for anyone to download. We can check our results by comparing them with those obtained by other scientists, so we are a little focus of real science. We are making a tiny contribution to understanding the Earth from within our classroom."
* Email: firstname.lastname@example.org
To join the SpiNet seismic network: www.scieds.comspinet