Dangerous pinwheel

Earth could be in for a neighborhood dispute with a death star, according to an Australian astronomer. A spectacular rotating pinwheel system just down the astronomical road from Earth — 8,000 light years away — includes an unstable Wolf-Rayet star that could explode. Eight years ago, WR104 was discovered in the constellation Sagittarius by Sydney University astronomer Peter Tuthill.
A Wolf-Rayet star is the last step on the way to a supernova — the explosion of a star at the end of its life. Images from the Mauna Kea in Hawaii telescope show that every eight months the two stars at the centre of the pinwheel orbit each other, leaving a trail of hot gas, carbon and dust. "Viewed from Earth, the rotating tail appears to be laid out on the sky in an almost perfect spiral," Tuthill said. "It could only appear like that if we are looking nearly exactly down on the axis of the binary system." Tuthill and his team worry this box-seat view might put us in the firing line when the system finally explodes."Sometimes, supernovae like the one that will one day destroy WR104 focus their energy into a narrow beam of very destructive gamma-ray radiation along the axis of the system," he warns. "If such a 'gamma-ray burst' happens, we really do not want Earth to be in the way." Even a short gamma-ray burst at supernova strength could zap away half the Earth's ozone layer, drastically increasing the amount of deadly space radiation that penetrates our atmosphere. One leading theory blames the Ordovician mass extinction of 443 million years ago on such an interstellar gamma-ray burst. There's no need to move planets just yet, however, because Tuthill is uncertain whether Earth is precisely on WR104's axis. We probably have hundreds of thousands of years before it blows, so we have plenty of time to come up with some answers," he said.
Tuthill's research is published in the latest edition of the Astrophysical Journal.



University of Sydney
A composite of 11 images of Wolf-Rayet 104, an unstable binary star system that could direct a deadly burst of gamma rays at Earth.

Sudden Global Cooling Has Scientists Perplexed

The past year has seen extraordinary and unexpected global cooling--inconsistent with global warming models, but completely consistent with the Superstorm model of how new ice ages begin.
For Great Britain, Ireland and Scotland, 2007 was a year without a summer. China has had its coldest winter in a hundred years. North America's snow cover is the most extensive in 50 years. The Antarctic is experiencing its coldest summer on record. It snowed in Baghdad for the first time in memory, and most of the world has seen exceptional and record breaking cold, and, across the US midwest, the most violent winter tornadoes ever recorded.
While scientists caution that this may or may not represent a trend, it is strikingly similar to conditions that appeared during the Little Ice Age that lasted into the 1740s, when there were very few sunspots and solar radiation appeared to decline.
At present, even though a sunspot of the type that usually heralds the beginning of a new solar maximum was observed in February, the sun's face has remained totally absent of sunspots.
While measurement of solar output is in its infancy, it is believed that solar variability is a major factor in the cycle of ice ages separated by brief interglacials that earth has been experiencing for the past three million years.
During the Little Ice Age, greenhouse gas levels in earth's atmosphere were low, with the result that the cooling resulted in ferocious winters and short summers, but not the extreme weather that has characterized past collapses from interglacial conditions to a new ice age.
That may not be true this time. Time will tell...

Kangaroo cull

Australia should do everything in its power to avoid culling hundreds of kangaroos in Canberra, Greens leader Bob Brown says.Defence Department contractors are preparing to cull about 400 kangaroos on a former naval site at Belconnen, in Canberra's north.
A report to the ACT government released last week recommended the cull go ahead without delay to protect lowland native grasslands and threatened species. The plan has drawn international condemnation by animal activists including British group Viva! which has the support of celebrity rock stars Sir Paul McCartney and Chrissie Hynde. Expert advice to the ACT government said relocating the animals would be inhumane, but Senator Brown said on Thursday he did not think that option had been properly explored. "In the report given to ACT government, it's dismissed in one paragraph, but the reasoning behind that dismissal is not there," Senator Brown told ABC Radio on Thursday. He is advocating a pilot program to relocate some of the animals to see if it is feasible. "Australia is coming into the spotlight over this, it's very rapidly becoming an international cause celebre. "We ought to be able to demonstrate to the world that we have done everything possible to obviate the need for killing 400 to 500 kangaroos." Senator Brown said a cull should go ahead only if a pilot program was unsuccessful."If it's found that can't be done without a great deal of cruelty then we're left with no option," he said. But ACT Liberal senator Gary Humphries said Senator Brown was engaging in populist politics and scientists agreed a cull was necessary."They said translocation on this scale has not been tried before in Australia and it would not work," Senator Humphries told the ABC.He said a trial relocation program would be expensive and would take several months. "And, of course, while that trial is going on, the kangaroos will continue to overgraze that area which is the habitat of a number of endangered species."
I agree with Senator Humphries. They are a real problem on the road causing 75% of all road accident insurance claims in the ACT.