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Black hole at heart of our galaxy “will erupt next year”, say astronomers By Rob Waugh

A huge eruption lit up the skies on our planet two million years ago - coming from the black hole at the heart of the Milky Way.

A huge eruption lit up the skies on our planet two million years ago - creating a fuzzy ball of light around the size and brightness of the moon.

The eruption - a huge blast from the black hole at the centre of our galaxy - would have been witnessed by our ancestors, homo erectus, on the plains of Africa.

Scientists have found the first evidence of this “huge explosion” of radiation from the supermassive black hole - four million times the mass of our sun - a faint glow in a cloud of gas millions of miles from the black hole itself.

Scientists describe the supermassive black hole - Saggitarius A* - as a “dormant volcano”.

Blasts of energy can jet out of black holes when stars and gas clouds are “consumed” by the black hole - and scientists warn that there are “lots and lots” circling our galactic centre.

One in particular could erupt next year.

"They have been monitoring a cloud and predict that it will fall into the black hole at some point in the next year; however, the amount of material will be far less than the event that illuminated the stream," said Greg Madsen, astronomer at the University of Cambridge.

"It will be much fainter and will pose no threat to Earth, but several powerful telescopes will be poised and ready to watch what happens."

Astronomers have long suspected that a large explosion occurred millions of years ago - but have never been able to prove it.

The evidence comes from a lacy filament of gas, mostly hydrogen, called the Magellanic Stream. This trails behind our galaxy’s two small companion galaxies, the Large and Small Magellanic Clouds.

“For twenty years we’ve seen this odd glow from the Magellanic Stream,” said Professor Joss Bland-Hawthorn, of the University of Sydney, who led a team studying this problem.

“We didn’t understand the cause. Then suddenly we realized it must be the mark, the fossil record, of a huge outburst of energy from the center of our galaxy.”

“It’s been long suspected that our galactic center might have sporadically flared up in the past. These observations are a highly suggestive ‘smoking gun’,” said Martin Rees, Astronomer Royal.

See Video Link Below:
http://uk.news.yahoo.com/video/death-star-hypernovas-black-holes-124614311.html

Death Star: Hypernovas and Black Holes

Stan Woosely, a scientist at the university of California, tries to identify where the powerful explosions in the universe are coming from, where stars are dying and where black holes are being born. From BBC science show Death Star.

The team gives its arguments in a paper accepted for publication in The Astrophysical Journal. Professor Bland-Hawthorn will speak about the work at the Galaxy Zoo meeting in Sydney, Australia, on 24 September.

The galaxy’s supermassive black hole has been known for decades. It’s orbited by a swarm of stars whose paths let us measure the black hole’s mass: four million times the mass of the Sun.

The region around the black hole, called Sagittarius A* [“A-star”], pours out radio waves, infrared, X-rays and gamma rays.

Flickers of radiation rise up when small clouds of gas fall onto the hot disk of matter that swirls around the black hole.

But evidence has been building of a real cataclysm in the past. Infrared and X-ray satellites have seen a powerful ‘wind’ (outflow) of material from this central region. Antimatter boiling out has left its signature. And there are the ‘Fermi bubbles’ -- two huge hot bubbles of gas billowing out from the galactic center, seen in gamma-rays and radio waves.

“All this points to a huge explosion at the center of our galaxy,” said team member Dr. Philip Maloney of the University of Colorado in Boulder, USA.

Scientists studying the galactic center came together at a workshop at Stanford University in California earlier this year.

While at the workshop, Professor Bland-Hawthorn realized the Stream could be holding the memory of the galactic center’s past.

See Video Link Below:
http://uk.news.yahoo.com/video/death-star-huge-explosion-deep-093411297.html

Death Star: Huge explosion in deep space

On 2nd July 1967, a satellite picked up a huge burst of gamma rays. Was it evidence of a nuclear bomb test in space? Or was it from a much bigger explosion in deep space? Can Einstein's famous physics equation E=MC2 help?

Struck by the fiery breath of Sagittarius A*, the Stream is emitting light, much as particles from the Sun hit our atmosphere and trigger the colored glows of the aurorae -- the Northern and Southern Lights.

The brightest glow in the Stream comes from the region nearest the galactic center.

Geometry, the amount of energy from the original flare from Sagittarius A*, the time the flare would take to travel to the Magellanic Stream, the rate at which the Stream would have cooled over time -- “it all fits together, it all adds up,” says team member Dr. Greg Madsen of the University of Cambridge in the UK.

Scientists say that such flares can and will happen again.

“There are lots of stars and gas clouds that could fall onto the hot disk around the black hole,” says Professor Bland-Hawthorn. “There’s a gas cloud called G2 that we think will fall in next year. It’s small, but we’re looking forward to the fireworks!”

Researchers say long-lost Leonardo may have been found

FLORENCE (Reuters) - Art researchers and scientists said on Monday that a high-tech project using tiny video probes has uncovered evidence that a fresco by Renaissance master Leonardo da Vinci lost for five centuries may still exist behind a wall of Florence's city hall.

Researchers work on the "Battle of Angiari" project to find a lost Leonardo da Vinci fresco. Photo credit:Reut

"Together with art historians and scientists combining historical evidence and technology, this research team has unlocked a mystery that has been with us for more than 500 years," said Terry Garcia, an executive vice president of the U.S. National Geographic Society, which sponsored the research.

The project to find what has come to be known as the "Lost Leonardo" has been controversial, in part because researchers had to drill several holes into an existing work and because not all agree that the Leonardo fresco is still there.

At the start of the 16th century, Florence's leaders commissioned Leonardo, then at the height of his career, to paint a massive fresco celebrating the Florentine Republic's victory over the Milanese in a battle on the plains of Anghiari that took place on June 29, 1440.

Leonardo, who loathed war as "a most beastly madness," depicted a group of horses and riders furiously fighting.

A banner promotes the "Battle of Angiari" project in Florence. Photo credit: Reuters

He abandoned the project a year after he started, probably because a new experimental technique for frescoes failed. But some of his preparatory studies remain, as well as other artists' copies of the original fresco.

All traces of the original were lost more than 50 years later when Giorgio Vasari renovated the great Sala dei Cinquecento in Florence's Palazzo Vecchio and was ordered to paint a new fresco, "The Battle of Marciano," to accommodate the higher walls.

Some believe that Vasari was loathe to destroy Leonardo's work, so he built a new wall with an air gap of several centimetres in front of the Leonardo in order to preserve what was left.

MEDICAL-STYLE PROBE
Researchers used tiny, medical-style endoscopic probes And other high-tech tools inserted through existing cracks in the outer wall holding the Vasari fresco and took samples of substances.

"We found traces of pigments that appear to be those known to have been used exclusively by Leonardo," said Maurizio Seracini, an engineer and expert in art diagnostics who has been on the trail of the "Lost Leonardo" for three decades.

"These data are very encouraging," he said, adding that one black pigment found was believed to be of the same type used by Leonardo on the Mona Lisa.

A high-tech project uses tiny video probes to find a long-lost Leonardo Da Vinci painting. Photo credit: Reute …

The research work was carried out by the U.S. National Geographic Society, the Center of Interdisciplinary Science for Art, Architecture and Archaeology at the University of California at San Diego and Italian art officials.

"I am quite convinced that something has been found and I think this is a historic day," Garcia said in an interview with Reuters at the presentation of the results.

"There is overwhelming historic documentation that indicates that the Leonardo was painted, that it was behind the wall and that it was in existence at the time that Vasari painted his fresco," he said.

"Then through a series of scientific analysis using state-of-the-art imaging technology we were able to determine that there was a wall in front of the original wall and we confirmed it visually with the endoscope that showed that there is a gap ... and the sample from the wall clearly indicates that there are pigments behind this," he said.

NEXT STEPS UNCERTAIN
He said it was now up to Italy's culture ministry to decide the next steps and if to explore other parts of the wall.

"We can't tell you today the condition of the Leonardo. That is for subsequent research and exploration," Garcia said. "Whatever remains of the Leonardo is behind that wall."

But some art historians are sceptical, saying the fresco of Battle of Anghiari was most likely destroyed before Vasari painted his new fresco.

A Leonardo da Vinci fresco may still exist behind a wall in Florence's city hall. Photo credit: Reuters

Some art historians working on the project withdrew their support and Italia Nostra, Italy's leading nature and arts conservation group, asked Florentine authorities to halt it because they said it risked harming the Vasari fresco and because they believed it was unlikely that the original Leonardo was there.

Garcia dismissed the criticism. "I think we have demonstrated that those who said the Leonardo was not behind the wall are wrong," he said.

"All of the holes that were put into the mural were either in areas that had been previously restored or in fissures, so the original Vasari was not touched," he said.

But even some of the participants at the presentation urged caution.

"We need further certainties and maximum protection for the Vasari fresco," said Cristina Acidini, arts superintendent for Florence, in response to a question about what the next step would be.

"There are pros and cons about every art project," said Marco Chatti, head of the Opificio Delle Pietre Dure, Florence's most prestigious arts restoration laboratory.

Florence mayor Matteo Renzi said more work needed to be done on the project to reveal the condition of the Leonardo, which he believes is behind the wall.

"I ask the government to authorise us to find out how much (of the Leonardo) is left, in what condition it is in, and to evaluate if we can bring this work of Leonardo back into the light for the whole world," Renzi said.

The mayor said he believed that modern technology should allow the public to appreciate both the Leonardo and Vasari.

"But if I had to choose, I would choose Leonardo," Renzi said.
(Additional reporting by Silvia Ognibene, editing by Paul Casciato)

Researchers say long-lost Leonardo may have been found

FLORENCE (Reuters) - Art researchers and scientists said on Monday that a high-tech project using tiny video probes has uncovered evidence that a fresco by Renaissance master Leonardo da Vinci lost for five centuries may still exist behind a wall of Florence's city hall.

Researchers work on the "Battle of Angiari" project to find a lost Leonardo da Vinci fresco. Photo credit:Reut

"Together with art historians and scientists combining historical evidence and technology, this research team has unlocked a mystery that has been with us for more than 500 years," said Terry Garcia, an executive vice president of the U.S. National Geographic Society, which sponsored the research.

The project to find what has come to be known as the "Lost Leonardo" has been controversial, in part because researchers had to drill several holes into an existing work and because not all agree that the Leonardo fresco is still there.

At the start of the 16th century, Florence's leaders commissioned Leonardo, then at the height of his career, to paint a massive fresco celebrating the Florentine Republic's victory over the Milanese in a battle on the plains of Anghiari that took place on June 29, 1440.

Leonardo, who loathed war as "a most beastly madness," depicted a group of horses and riders furiously fighting.

A banner promotes the "Battle of Angiari" project in Florence. Photo credit: Reuters

He abandoned the project a year after he started, probably because a new experimental technique for frescoes failed. But some of his preparatory studies remain, as well as other artists' copies of the original fresco.

All traces of the original were lost more than 50 years later when Giorgio Vasari renovated the great Sala dei Cinquecento in Florence's Palazzo Vecchio and was ordered to paint a new fresco, "The Battle of Marciano," to accommodate the higher walls.

Some believe that Vasari was loathe to destroy Leonardo's work, so he built a new wall with an air gap of several centimetres in front of the Leonardo in order to preserve what was left.

MEDICAL-STYLE PROBE
Researchers used tiny, medical-style endoscopic probes And other high-tech tools inserted through existing cracks in the outer wall holding the Vasari fresco and took samples of substances.

"We found traces of pigments that appear to be those known to have been used exclusively by Leonardo," said Maurizio Seracini, an engineer and expert in art diagnostics who has been on the trail of the "Lost Leonardo" for three decades.

"These data are very encouraging," he said, adding that one black pigment found was believed to be of the same type used by Leonardo on the Mona Lisa.

A high-tech project uses tiny video probes to find a long-lost Leonardo Da Vinci painting. Photo credit: Reute …

The research work was carried out by the U.S. National Geographic Society, the Center of Interdisciplinary Science for Art, Architecture and Archaeology at the University of California at San Diego and Italian art officials.

"I am quite convinced that something has been found and I think this is a historic day," Garcia said in an interview with Reuters at the presentation of the results.

"There is overwhelming historic documentation that indicates that the Leonardo was painted, that it was behind the wall and that it was in existence at the time that Vasari painted his fresco," he said.

"Then through a series of scientific analysis using state-of-the-art imaging technology we were able to determine that there was a wall in front of the original wall and we confirmed it visually with the endoscope that showed that there is a gap ... and the sample from the wall clearly indicates that there are pigments behind this," he said.

NEXT STEPS UNCERTAIN
He said it was now up to Italy's culture ministry to decide the next steps and if to explore other parts of the wall.

"We can't tell you today the condition of the Leonardo. That is for subsequent research and exploration," Garcia said. "Whatever remains of the Leonardo is behind that wall."

But some art historians are sceptical, saying the fresco of Battle of Anghiari was most likely destroyed before Vasari painted his new fresco.

A Leonardo da Vinci fresco may still exist behind a wall in Florence's city hall. Photo credit: Reuters

Some art historians working on the project withdrew their support and Italia Nostra, Italy's leading nature and arts conservation group, asked Florentine authorities to halt it because they said it risked harming the Vasari fresco and because they believed it was unlikely that the original Leonardo was there.

Garcia dismissed the criticism. "I think we have demonstrated that those who said the Leonardo was not behind the wall are wrong," he said.

"All of the holes that were put into the mural were either in areas that had been previously restored or in fissures, so the original Vasari was not touched," he said.

But even some of the participants at the presentation urged caution.

"We need further certainties and maximum protection for the Vasari fresco," said Cristina Acidini, arts superintendent for Florence, in response to a question about what the next step would be.

"There are pros and cons about every art project," said Marco Chatti, head of the Opificio Delle Pietre Dure, Florence's most prestigious arts restoration laboratory.

Florence mayor Matteo Renzi said more work needed to be done on the project to reveal the condition of the Leonardo, which he believes is behind the wall.

"I ask the government to authorise us to find out how much (of the Leonardo) is left, in what condition it is in, and to evaluate if we can bring this work of Leonardo back into the light for the whole world," Renzi said.

The mayor said he believed that modern technology should allow the public to appreciate both the Leonardo and Vasari.

"But if I had to choose, I would choose Leonardo," Renzi said.
(Additional reporting by Silvia Ognibene, editing by Paul Casciato)