For years, astronomers have known that Sun-like stars lose most of their mass as they transition to the red giant stage, but this occurrence remained unexplainable. That is, until an international team of astronomers believes that they have solved the mystery. This discovery can shed light on stellar evolution and, more specifically, how stars age.

When stars like our Sun turn into red giants, they shed off their outer shells of gas and expand and become hundreds of times larger. Stars have “atmospheres,” which consist of powerful winds of gas and dust (which makes up much of a stars’ mass) that the stars emanate, and during their transition, the winds become 100 million times more violent. These “superwinds” occur for 10,000 years – the length of time during which usually red giants live – and cause stars to lose more than half their mass or as much so that only their cores remain.

What causes the “superwinds” has remained elusive for astronomers. Before, it had been thought that the amount of light from the red giants (which are considerably bright for main sequence stars) was absorbed by the dust grains, which were then pushed out by the light. However, all the models that were produced did not coincide with this theory.

The team consists of astronomers from the University of Manchester, Oxford and Macquarie University, University of Sydney, Australia, Paris-Diderot University, and New South Wales. Using the European Southern Observatory’s (ESO) Very Large Telescope (VLT) in northern Chile, the team looked at dying stars with a powerful resolution that allowed them to see the stars’ winds. They were surprised to see how many dust grains whirled around and how large they were. However, they were no bigger than grains of sand, but they were large for their size.

Using this information, the team was able to discover that these dust grains acted as mirrors, reflecting light from other stars. Since the grains remain cold, the star is able to push them out at 10 kilometers per second (20 million miles per hour).

“The dust and sand in the superwind will survive the star and later become part of the clouds in space from which new stars form,” Professor Albert Zijlstra, from the University of Manchester’s Jodrell Bank Observatory, said in the University of Manchester’s news release.

“The sand grains at that time become the building blocks of planets,” he continued. “Our own Earth has formed from star dust. We are now a big step further in understanding this cycle of life and death.”

Now that the mystery of superwinds has been solved, there is another for astronomers to figure out: how these dust grains form and are able to exist at their large size so close to the stars.

The article “Superwinds” of Older Stars Explained appeared first on The Toonari Post - News, Powered by the People!.

Mimas, an academic data centre based at the University of Manchester which provides researchers in the UK with key information assets, has launched a new pioneering search and discovery platform on behalf of JISC Collections – JISC Historic Books, powered by Autonomy IDOL (Intelligent Data Operating Layer).

This new platform gives the UK academic community access to vast amounts of digitized content across a wide range of disciplines. This revolutionizes research in the UK by suggesting relevant content automatically and in real time, and opens up a world of resources to students and researchers.

“Autonomy’s ability to infinitely scale is absolutely central to the project,” said Vic Lyte, Head of Technology Services at Mimas. “It is easy for us to add new content as and when needed, and IDOL automatically works its magic by understanding concepts within the data and serving it up to the appropriate users according to what they are looking for.

This represents a massive advance for the research community, showing, for the first time in this sector, how meaning based technology can be used to unlock some of our country’s most valuable assets – its literature.”

JISC Historic Books contains the full text or page images of over 300,000 books published in Britain before 1800. The service, developed for JISC Collections and the British Library, draws content from two of the best-known and longest-established early book collections, Early English Books Online (EEBO) and Eighteenth Century Collections Online (ECCO).

This is combined with the British Library Nineteenth Century Collection, offering digitized versions of more than 65,000 original editions from the nineteenth century, covering philosophy, history, poetry and literature. The collection extends to over 25 million pages of rare and previously inaccessible content.

“The new platform brings together digitized collections of historic books which are otherwise distributed on different publisher platforms or not otherwise available,” explained Lorraine Estelle, CEO of JISC Collections. “It provides UK academic researchers and students with a single sign-on and interface to a vast corpus of primary source material.”

“We’re delighted that JISC Historic Books, and our partnership with JISC, JISC Collections and Mimas, enable Higher Education users to explore and research many thousands of texts – whether they’re classics or the hitherto more obscure end of the spectrum,” says Caroline Brazier, the British Library’s Director of Scholarship and Collections.

“Shelves and shelves of books, that could previously only be read in our St Pancras Reading Rooms, by one reader at a time, are now simultaneously and instantly available to thousands of JISC eCollections members’ users.”

“Autonomy’s unique ability to understand meaning in information is transforming the way researchers and users access and interact with content, opening the possibility to solve some of the great academic questions,” said Nigel Hutchinson, VP Autonomy Power Solutions, EMEA.

JISC Journal Archives, also part of the JISC eCollections service, uses IDOL to provide meaning based discovery across more than 3.75 million articles from the archives of over 600 journals of major publishers and societies, such as Taylor & Francis, Royal Society of Chemistry, Oxford University Press, ProQuest, Institute of Physics, Institution of Civil Engineers, Brill, and Cambridge University Press.

The article Revolutionary Online Research Platform Goes Live in the UK appeared first on The Toonari Post - News, Powered by the People!.