Ultima Thule

In ancient times the northernmost region of the habitable world - hence, any distant, unknown or mysterious land.

Sunday, August 20, 2006

Gather ye rosebuds while ye may, Old Time is still a-flying;

By Aussiegirl

And Robert Herrick continues thus:

And this same flower that smiles to-day
To-morrow will be dying.

The glorious lamp of heaven, the sun,
The higher he's a-getting,
The sooner will his race be run,
And nearer he's to setting.

This seemed an appropriate poem to quote, given the rather gloomy first sentence from this article: IT WILL be 70 billion years before the lights start to go out all over the universe, scientists at a Scottish university revealed yesterday. Still, you can gather a lot of rosebuds in 70 billion years, and, who knows, given how physical theories have changed and ever more strange objects have been postulated, maybe they'll find new sources of energy, and after such a long period of time the universe will be off and running for even more years.

Scotsman.com News - Sci-Tech - Universe has fuel for another 70bn years

Universe has fuel for another 70bn years

IT WILL be 70 billion years before the lights start to go out all over the universe, scientists at a Scottish university revealed yesterday.

Researchers at St Andrews, together with colleagues in Germany and Australia, have discovered that the universe is slowing the rate at which it creates stars. When the process stops, the universe will black out.

Tracking down matter created during the Big Bang 14 billion years ago has provided cosmologists with one of their greatest challenges for many years.

The survey searched more than 10,000 giant galaxies, each comprising of up to ten billion stars as well as "bulges, discs and super-massive black holes".

Project leader Dr Simon Driver, director of St Andrews University Observatory, said the group had managed to "dismantle" these galaxies in order to study each individual component.

They discovered that 20 per cent of matter had already become stars - meaning the universe has already "guzzled" its way through about a fifth of its original fuel reserves. Dr Driver said: "The simplest prognosis is that the universe will be able to form stars for a further 70 billion years or so after which it will start to go dark.

"However, unlike our stewardship of the Earth, the universe is definitely tightening its belt with the rate at which new stars are forming steadily decreasing."

The results of the survey show that around 20 per cent of the universe's original fuel reserves is locked up in stars. A further 0.1 per cent lies in dust expelled from the massive stars from which solid structures including planets such as Earth as well as man are made. And about 0.01 per cent is in the form of super-massive black holes.

Dr Driver said: "The remaining 80 per cent are almost completely in gaseous form lying both within and between the galaxies and constitute the reservoir from which future generations of stars may form."

The ground-breaking report has resulted in the creation of the Millennium Galaxy Catalogue (MGC), constructed from more than 100 nights spent using high-powered telescopes in the Canary Islands, Australia and Chile.

Dr Driver said: "What is new about the MGC is that it focuses on the structures in which stars are arranged inside galaxies. We have literally dismantled each galaxy so that we can study the main components separately."

The survey is the first to catalogue reliable information on the distances, sizes, colours and shapes of both the bulge and disc components of so many galaxies.

Dr Driver and his team found that on average half the stars in the universe lie in the central bulges of galaxies, while the other half are found in discs surrounding the bulges.

Dr Alister Graham, of the Australian National University, added: "By measuring the concentration of stars in each galaxy's bulge, we have also been able to determine the super-massive black hole mass at the heart of each galaxy.

"It was then a simple matter of summing these up to determine how much of the Universe's matter is locked away in such monstrous black holes."

The survey was presented at the general assembly of the International Astronomical Union in Prague.


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