'Aerogel' set to star at science show
It is the lowest-density solid known to man. Recorded in the "Guinness Book of World Records", it is about 99 per cent air. But this material is so strong it can theoretically support 4,000 times its own weight.
It is nicknamed "frozen smoke", "solid smoke" or "blue smoke" as a result of its semi-transparent nature and the way it scatters light. It feels like Styrofoam to the touch. It is aerogel and, unlike conventional foam, this sponge-like material has extreme porosity and is composed of a network of interconnected nano-particles. Thanks to its unusual properties - such as low thermal conductivity - NASA has used aerogel on the Stardust spacecraft and the Mars Rover. If you want see what it looks like and experience its strength, amazing aerogel will be on display at the National Science and Technology Fair 2006 at Bitec from Friday until August 22. Caretaker Science and Technology Minister Pravich Ratanapian said Nasa would bring 10 square centimetres of aerogel to the exhibition. Aerogel is a low-density solid-state material derived from gel in which the liquid component has been replaced with gas. Created by high temperatures and pressure-critical-point drying, aerogel is 1,000 times less dense than glass and is heat resistant to 1,500 degrees Celsius. Onboard Stardust, aerogel captured comet samples and interstellar dust that were smaller than grains of sand. Without aerogel, they could have been altered in shape and chemical composition - or even vaporised. To collect particles without damaging them, Nasa placed aerogel on the head of the spacecraft. Once a particle hits aerogel, it buries itself. Scientists can then carry out detailed analysis. As well as aerogel, Pravich said the science exhibition would feature robots. Last year the therapeutic robot seal called Paro came alone. This year several of its friends will accompany it. Developed as a pet, Paro can mimic animal behaviour and even develop its own character. Two other kinds of robot, PaPeRo and Wakamaru, will feature, too. PaPeRo is a personal robot made by NEC. It will show off by pulling natural facial expressions and remembering its owner's interests and preferences. It can recognise 650 phrases and speak more than 3,000. With the latest image-recognition technology, PaPeRo has the ability to recognise people's faces. Mitsubishi's Wakamaru is a friendly robot. Last year it worked as the receptionist at the World Expo in Aichi, Japan. It can speak four languages and is learning Thai. Other highlights include a simulation of an earthquake with a full light-and-sound show, to allow exhibition goers to come face to face with natural disasters.
Pongpen Sutharoj The Nation
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