A SUMMER internship to learn more about astrophysics turned into a stunning coup for Monash undergraduate Amelia Fraser-McKelvie when she helped solve one of the big mysteries of science.
Astrophysicists have long been baffled by a belief that the universe must have a greater mass than is visible in the planets, dust and stars that make up much of what can be seen. But they had no way of proving it. They estimated that about half the mass required to keep the universe functioning as it does was ''missing''.
Ms Fraser-McKelvie found some, and her discovery will aid the development of telescopes in Australia.
The 22-year-old aerospace engineering student, who works with Monash astrophysicists Kevin Pimbblet and Jasmina Lazendic-Galloway, explained.
''If we're looking very, very long distances from Earth we're detecting mass, but if we're looking closer to Earth we only see about half the mass that we're expecting to see,'' she said. ''This is what is called the missing mass problem.
''People have theorised that this mass has settled in filaments that extend between clusters of galaxies, so we tested and confirmed this prediction by detecting it in the filaments.''
Ms Fraser-McKelvie was selected this past summer as an intern for a six-week astrophysics research project and was quite surprised when she stumbled across the missing mass, at first not realising she had found it.
After showing her work to Dr Lazendic-Galloway, its significance became clear.
''It was definitely the result of my supervisors pushing me hard and we got a good result, but it was a big surprise,'' she said. ''Using her expert knowledge in the X-ray astronomy field, Jasmina re-analysed our results to find that we had, in fact, detected the filaments in our data, where previously we believed we had not.''
Dr Pimbblet said scientists had made a number of assumptions about what the mystery mass might be like, but none had actually found it.
''It was thought from a theoretical viewpoint that there should be about double the amount of matter in the local universe compared to what was observed,'' he said.
''It was predicted that the majority of this missing mass should be located in large-scale cosmic structures called filaments - a bit like thick shoelaces.''
Dr Pimbblet said the mass was also expected to be low-density, but very hot - roughly 1 million degrees celsius. He said Ms Fraser-McKelvie's work had proved those predictions right.
''The question of what the universe is made of, and how it evolves over time, are old questions that even today remain not fully answered,'' he said.
''This research contributes to those questions by detecting an extra portion of 'normal' matter that was predicted to exist in theory.''
Dr Pimbblet said the discovery had significant practical applications and could change the way telescopes were built.
''I cannot underscore enough what a terrific achievement this is,'' he said.
''We will use this research as a science driver for future telescopes that are being planned, such as the Australian Square Kilometre Array Pathfinder, which is being built in outback Western Australia.''
The trio published a research paper on the missing mass in one of the world's oldest and most prestigious scientific journals, Monthly Notices of the Royal Astronomical Society.
Ms Fraser-McKelvie said she was overwhelmed at having the paper published, and the opportunities that came with it.
''It's very significant. I feel really lucky, I guess, to have this happen to me. It's a very big honour and I couldn't have done it by myself,'' she said.
The student will start her honours year under Dr Pimbblet in 2012, but said she did not know what the future would hold after that.
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