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Serious work can also be serious fun for physicist Danail Obreschkow.

While the Research Associate Professor at the International Centre for Radio Astronomy Research is floating around and having fun at zero gravity, his team's experiments are helping them to understand how to harness the energy that is concentrated in a bursting bubble.

"It sounds so simple, and perhaps also a bit of fun," Professor Obreschkow said. "Why wouldn't we understand the physics of a bubble in the 21st century?"

There is so much energy at the point of collapse of a bubble that it can produce chemical reactions, it can create shock waves, it can (eventually) erode steel and it can dissolve kidney stones.

To understand the complex process and harness its energy most effectively, Professor Obreschkow and his team (who are dispersed around the world, in Switzerland, Cambridge and Vietnam) need to study the effects of gravity on bubbles. So their experiments are done at zero gravity, while they enjoy weightlessness.

The team is just one of up to 15 groups which, next month, will board a specially-modified A300 aircraft at Merignac in the Bordeaux region of France to take a zero gravity flight.

"The plane has been completely emptied out and refitted for scientists to do research that requires weightlessness," Professor Obreschkow said. "There are lots of studies in human biology and human psychology."

Professor Obreschkow is the co-ordinator of his team's research, using gas bubbles in water to learn how they grow and collapse.

"Collapsing bubbles can cause a lot of damage. Even big ships with huge propellers need to have them replaced every year because the bubbles in the ship's wake erode the surface of the propeller.

"They also cause problems in hydro-energy production. The water rushes so fast through the generators that bubbles are produced and collapse, and erode the generators."

But the energy of a burst bubble can also be useful. "You can use speakers to produce sound waves that create bubbles in a human body and those bubbles can destroy a kidney stone."

The process of a collapsing bubble can also help astronomers at ICRAR understand how stars explode. "In both processes, jets are created at the point of collapse or explosion," he explained.

"We hope our research will help us to work out how to curb the erosive feature of collapsing bubbles; how to optimise the advantages, such as in dissolving kidney stones; and to learn more about how stars explode," he said.

Professor Obreschkow will go to his homeland of Switzerland within the next week or so to help build the team's latest experiments. They will then take a week to install their equipment in the plane. The European Space Agency will conduct three zero gravity flights in the last week of May. Two or three members of the team will go on each flight.

"The plane will head off from Merignac to French military airspace, either above the Mediterranean or the Atlantic, depending on weather conditions. Then, it will speed up to the speed of sound, the pilot will pull up the nose of the aircraft and turn off the engine. Then the plane will go up, travel for 24 seconds at zero-g, then come down, in a parabolic curve, just like a stone that is thrown into the air.

"That procedure is repeated 30 times. In between each parabolic curve, we have time to check our experiments, analyse what's happened at zero-g and make adjustments for the next period."

Professor Obreschkow has done the weightless flights four times before and enjoys them. "At the end of the day, you are exhausted, but it is amazing. Some people get really sick and hate them, even though we all take medication to help us cope with the physical sensations."

He said that, as the plane climbed towards zero gravity, the passengers felt very heavy and weighed down. "You have to be careful to sit still and not move your head, otherwise you can make yourself sick. Then, suddenly, it is like dropping into an air hole as the plane levels out, your stomach flips, then ... you are weightless. There is no up and down. When you turn around, it feels as if you are staying still and everything around you is turning around.

"We usually have a lot of fun, spinning around, kicking each other. But you must take care not to be up on the ceiling of the plane when it dives down and you go back to hypergravity, from weightlessness to the feeling of being double heavy."

Published in UWA News , 30 April 2012