SA scientists win top EU prize

2007-03-12 13:36

Johannesburg - South African scientists' research on gamma rays has helped an international astronomy team win a top European Union award - and their technology could be in your washing machine.

"We effectively stood in the shoes of people like Galileo," said Professor Okkie de Jager of North West University (NWU) in Potchefstroom on Monday.

"We opened a new window on the universe, one that was not open before."

De Jager and four other scientists at NWU are part of an EU-funded team of about 100 which runs the High-Energy Stereoscopic System (HESS), four telescopes in Namibia used to research gamma rays.

The team won the prestigious EU Descartes prize for research for 2006, announced on March 7 in Belgium.

'Revolutionised techniques'

"The High Energy Stereoscopic System... has revolutionised existing astronomical observation techniques and increased our knowledge and understanding of the Milky Way and beyond," said the EU.

"With EU support they have designed and built the system, developed the complex software needed to collect and analyse data and offered training to young astronomers and astrophysicists."

The gamma rays seen by HESS are of extremely high energies and emanate from the resurrected remnants of stars that have died.

The HESS team pinpointed the source of these rays in the Milky Way, the galaxy which contains the Earth.

De Jager said the rays are so energetic that they cause a shock wave in the Earth's atmosphere, which is seen as a blue disc of light called Cherenkov light. It is this light that the scientists measure.

When looking at the Milky Way, the astronomers are examining rays from remnants of stars which died anything from 1000 to 50 000 years ago.

"What we see are stars that have exploded," said De Jager.

When a star explodes, it "re-energises" its environment, leaving a rapidly-rotating neutron star with a nebula.

Useful spin-offs

The team cannot bring these nebulae and black holes into the laboratory to examine, so scientists have to develop mathematical models and technology to simulate them.

"We develop mathematical skills and problem-solving techniques which allow us to solve very difficult problems," said De Jager.

One of the more unusual benefits was the development of technology now used in ozone washing machines, which makes it possible to get a cleaner wash using cold water - a substantial reduction in energy use.

These novel technologies also open new possibilities for ultra-fast ignition systems in the automotive industry, which should result in cleaner combustion.

Now the team is working on HESS 2, a 30-metre telescope to join the other HESS telescopes in Namibia, and the Department of Science and Technology hopes to add more South Africans to the team.

The €330 000 prize from the Descartes award is going towards building HESS 2.

"It will be the world's largest reflector for astronomical purposes," said De Jager.

- SAPA