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Two NZ astronomers from UC to study the universe through world's biggest telescope

Thursday 17 January 2013, 3:21PM

By University of Canterbury

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Two New Zealand astronomers from the University of Canterbury (UC) have been successful in applying to research the universe through the world's biggest astronomical project.

UC's Dr Loretta Dunne and Dr Steve Maddox have been awarded time on the Atacama Large Millimetre Array telescope (ALMA) in Chile. ALMA received 1100 proposals from all over the world and 200 were given time to use the facility.

``It is a very competitive facility because it is so much more powerful than anything previously built anywhere in the world,'' Dr Dunne said today.

``Out of the 200 successful proposals only two were from countries not involved in building ALMA. One of those was ours. It's great for New Zealand that astronomers here can get competitive time on a world class facility.

`` ALMA is an array of 66 antennae located high in the Atacama desert at 5000 metres above sea level.  It operates at millimetre wavelengths and can take 3D pictures of gas and dust surrounding nearby stars and in distant galaxies at exquisite angular resolution - better than the Hubble. This will allow us to piece together the complex interactions between stars and the gas from which they form.

``We're looking at galaxies which are being seen when the universe was three billion years younger than it is now or about 3.3 billion light years away. We are looking at the gas content of these galaxies to see how much fuel they have for forming new stars.''

Dr Dunne said galaxies had changed dramatically over cosmic time from incoherent messy patches of stars in the early universe to the complex and beautiful spiral and elliptical shapes seen today.

The UC astronomers want to piece together how galaxies evolve. They need to measure how and when they formed their stars and what determined bursts of star formation.

``To do this properly we need to measure how much gas there is inside galaxies at various times in the history of the universe since gas is the fuel from which stars form. However, it is very difficult to see this gas and, before ALMA, measuring the gas content of galaxies this far away was very difficult. ALMA is allowing us to probe the evolution of the gas inside galaxies for the first time.

``ALMA is such a revolutionary instrument in its scientific concept, its engineering design and its organisation as a global scientific endeavour.''

With its high resolution and sensitivity, ALMA has opened an entirely new window on the universe allowing scientists to unravel long standing and important astronomical mysteries in search of cosmic origins.