Aussie Student Solves Riddle for Scientists..Finds Universe's Missing Mass

This NASA illustration photo shows stars that are forming in a dwarf starburst galaxy

SYDNEY: A 22-year-old Australian university student has solved a problem which has puzzled astrophysicists for decades, discovering part of the so-called 'missing mass' of the universe during her summer break. Undergraduate student Amelia Fraser-McKelvie made the breakthrough during a holiday internship with a team at Monash University in Melbourne, locating the mystery material within vast structures in the intergalactic medium called filaments.

The paper has been accepted for publication in the Monthly Notices of the Royal Astronomical Society.
Monash astrophysicist Kevin Pimbblet explained that scientists had previously detected matter that was present in the early history of the universe but that could not now be located. "There is missing mass, ordinary mass not dark mass ... It was missing to the present day," said Pimbblet. "We didn;t know where it went. Now we do know where it went because that's what Amelia found."

"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. Pimbblet said astrophysicists had known about the 'missing' mass for the past two decades, but the technology needed to pinpoint its location had only become available in recent years.

Fraser-McKelvie, an aerospace engineering and science student, was able to confirm after a targeted X-ray search for the mystery mass that it had moved to the filaments of galaxies, which stretch across enormous expanses of space.

Pimbblet's earlier work had suggested the filaments as a possible location for the "missing" matter, thought to be low in density but high in temperature.  "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," said Pimbblet.

He said the discovery could drive the construction of new telescopes designed to specifically study the mass.
"I cannot underscore enough what a terrific achievement this is. 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."

Pimbblet admitted the discovery was primarily academic, but he said previous physics research had led to the development of diverse other technologies."The pure research has knock-on effects to the whole society which are sometimes difficult to anticipate. "Whenever I speak to people who have influence, politicians and so on, they sometimes ask me 'Why should I invest in physics pure research?'. And I sometimes say to them: 'Do you use a mobile phone? Some of that technology came about by black hole research'."

This discovery is important because it is another piece of the puzzle which is our universe. It's part of the story of how the universe was formed and how we came to be. I, for one, would like to know.