sexta-feira, 28 de setembro de 2012

New comet will light up the sky

This interplanetary visitor may be the brightest comet ever.

About a year from now, Comet C/2012 S1 (ISON) probably will become the brightest comet anyone alive has ever seen. How bright it could get is currently the subject of vigorous discussion among planetary scientists and everyday comet-watchers.

Two astronomers, Vitali Nevski from Vitebsk, Belarus, and Artyom Novichonok from Kondopoga, Russia, discovered the comet on images they obtained September 21. They used the 16-inch (0.4-meter) Santel reflector of the International Scientific Optical Network, whose abbreviation — ISON — is now the Comet C/2012 S1’s common name. When the two scientists found the comet, it glowed weakly at magnitude 18.8. As a comparison, it would take the light from more than 100,000 such comets to equal the faintest star visible to the naked eye from a dark site.

According to predictions, the comet will approach to within 0.012 astronomical units (1.1 million miles [1.8 million kilometers]) of the Sun at the end of November 2013. One astronomical unit (AU) equals the average distance between the Sun and Earth, about 93 million miles (149.7 million km). Then, in January 2014, the comet will approach to within 0.4 AU (37.2 million miles [59.9 million km]) of Earth.

Regarding visibility, Comet ISON — currently 6.5° due east of the 1st-magnitude star Pollux in Gemini the Twins — is now bright enough for amateur astronomers with large telescopes to image. That said, the comet itself will not show much in the way of detail for several months. By late summer 2013, observers at dark locations should be able to spot the comet through small telescopes or possibly even binoculars. And sometime in late October or early November, C/2012 S1 should cross the naked-eye visibility threshold. From there, it may reach — or even exceed — the brightness of the Full Moon.

When the comet is closest to the Sun (a moment astronomers call perihelion), it may shine a dozen times as brightly as Venus, normally the brightest “starlike” object in the sky. Unfortunately, on that date it will lie only 4.4° north of our daytime star, and the Sun’s glare may hide it from the view of casual observers.

Immediately after reaching perihelion, Comet ISON heads north. And while the comet fades as its distance from the Sun increases, it still should be as bright as Venus, but with a spectacular tail. Its position will allow observers all over Earth to see it, but those in the Northern Hemisphere will get the better views as Christmas approaches. In fact, on January 8, 2014, the comet will lie only 2° from Polaris — the North Star.


quinta-feira, 27 de setembro de 2012

Nazi space Buddha was meteorite, includes swastika

This space Buddha, also known as 'iron man' to the researchers, is of unknown age, though the best estimates date the statue to sometime between the eighth and 10th centuries.

It sounds like a mash-up of Indiana Jones' plots, but German researchers say a heavy Buddha statue brought to Europe by the Nazis was carved from a meteorite that likely fell 10,000 years ago along the Siberia-Mongolia border.

This space Buddha, also known as "iron man" to the researchers, is of unknown age, though the best estimates date the statue to sometime between the eighth and 10th centuries. The carving depicts a man, probably a Buddhist god, perched with his legs tucked in, holding something in his left hand. On his chest is a Buddhist swastika, a symbol of luck that was later co-opted by the Nazi party of Germany.

"One can speculate whether the swastika symbol on the statue was a potential motivation to displace the 'iron man' meteorite artifact to Germany," the researchers wrote online Sept. 14 in the journal Meteoritics & Planetary Science.

Iron man adventure

The iron man first came to Germany after a 1938-1939 Tibet expedition by zoologist and ethnology Ernst Schäfer, who was sent to the region by the Nazi party to find the roots of Aryan origin. The statue then passed into the hands of a private owner. [Fallen Stars: A Gallery of Famous Meteorites]

Stuttgart University researcher Elmar Bucher and his colleagues first analyzed the statue in 2007, when the owner allowed them to take five miniscule samples of it. In 2009, the team had the opportunity to take larger samples from the inside of the statue, which is less prone to contamination by weathering or human handling than the outside where the initial samples were taken.

They found that the statue is carved from a rare class of space rocks known as ataxite meteorites. These mostly iron meteorites have a high level of nickel. The largest-ever known meteorite, the Hoba meteorite of Namibia, is an ataxite meteorite that may weigh more than 60 tons.

It came from outer space

A chemical analysis of the iron man samples revealed they are a close match for a famous scattering of space rocks from the Siberia and Mongolian border. The Chinga meteorite field holds at least 250 meteorite fragments, most relatively small, though two topping 22 pounds (10 kg) have been found there. Scientists estimate the Chinga meteorite fell 10,000 to 20,000 years ago. The field's first discovery was recorded in 1913, but the statue's existence suggests people were mining the field for artistic materials long before that, Buchner said.

The identity of the carved man is unclear, but the researchers suspect he may be the Buddhist god Vaisravana, also known as Jambhala. Vaisravana is the god of wealth or war, and he is often portrayed holding a lemon (a symbol of wealth) or moneybag in his hand. The iron man holds an unidentified object in his hand. The statue is about 9.5 inches (24 cm) tall and weighs about 23 pounds (10.6 kg).

Many cultures used meteorite iron to make daggers and even jewelry, Buchner and his colleagues wrote, and meteorite worship is common among many ancient cultures. But the Buddha carving is unique.

"The Iron Man statue is the only known illustration of a human figure to be carved into a meteorite, which means we have nothing to compare it to when assessing value," Buchner said in a statement. "Its origins alone may value it at $20,000; however, if our estimation of its age is correct and it is nearly a thousand years old it could be invaluable."

Fonte: csmonitor

domingo, 23 de setembro de 2012

Meteorites, space junk - or alien invasion?

The sight of unexplained fireballs in the night sky had some Scots wondering if this would become The Day The Earth Stood Still due to an alien encounter Photograph: Thomas Heaton/

SOME said it looked like a scene from the film Independence Day, others feared an aeroplane was crashing – but most simply stared at the sky in awed bewilderment at one of the most amazing astronomical displays ever seen over Scotland.

The emergency services were flooded by calls as a suspected meteorite shower lit up the skies. However, astronomers are still not sure exactly what happened late on Friday night, with some saying it might not have been meteorites but burning space junk – the disintegrating remains of satellites – falling to earth.

Concerned members of the public from Airdrie to Arbroath likened the bright lights they saw to flares, fireworks and the flaming debris from an exploded aircraft.

The lights were seen as far north as Caithness and by islanders on Skye, with sightings also reported in parts of central Scotland, including in Edinburgh and Glasgow. Other sightings were reported across parts of England and Northern Ireland, with one Twitter user describing seeing a "huge fireball" over Newquay in Cornwall.

Coastguards and police up and down the country were inundated with calls from around 11pm as people witnessed the slow-moving fireballs streak across the night sky, with some describing a loud "sonic boom" effect as they passed.

A spokesman for Forth Coastguard said: "From talking to other stations and to the RAF it's almost certainly meteorite activity. Calls came in from all over the place, thick and fast. We've had people report possible plane crashes, and others the weirdest fireworks they've ever seen. Folk just haven't known how to describe what they've seen. It's quite extraordinary."

People from Crail, Johnshaven and Arbroath had contacted them.

Clyde Coastguard said it had also received a "wee flurry" of calls reporting flares over Drummore, Airdrie and Brodick on Arran.

A spokeswoman said: "When we get it all over and at the same time then we attribute them to meteorites. There was meteorite activity forecast from September 15 to 21."

Jodrell Bank Observatory in Cheshire tweeted that there was "no real consensus on whether last night's spectacular fireball was a space rock burning up or space junk (bit of spacecraft)".

The Met Office tweeted that it believed it had been a meteorite.

Shetland Coastguard said a report of a flare at 11.10pm at Duncansby Head near John O'Groats was thought to be part of the meteor shower. Meteorites are also known as shooting stars because when they enter the Earth's atmosphere they heat up and emit light, giving the impression of a flare.

Explosions and rumblings are often heard during meteorite falls, which can be caused by sonic booms, as well as shock waves as the meteorite disintegrates. These sounds can be heard over areas of up to several thousand square miles.

Nicola Hopkin in Newton Mearns in Glasgow said she saw a long, slow-moving trail of yellow fire with a burning red circular tip passing through the sky accompanied by two sonic booms. "It looked like a plane had blown up in mid-air and was crashing. It was moving at an odd angle and seemed very low in the sky," she said. "It was incredible to see but a little frightening as I didn't really understand what I was looking at – I couldn't work out if it was a plane, a rocket, a meteor, a comet or what. When it was just out of my line of sight I heard what I thought were two gun shots or cars backfiring. They must have been sonic booms."

Brian Guthrie in Grangemouth said it had appeared to be something "pretty large breaking up in the atmosphere", and added: "I've seen shooting stars and meteor showers before, but this was much larger and much more colourful."

The lights were also clearly seen throughout the north of England, with people in Sheffield, Manchester, Leeds, and Blackpool taking to Twitter to record the event.

Harry Walker, 14, near Barnsley in South Yorkshire, said: "It appeared to be low in the sky and took quite a while to fly across the horizon. It was amazing. We didn't know what we had seen but then everyone on Twitter was calling it a meteor."

Tim O'Brien, associate director of the Jodrell Bank Observatory, said: "It was probably 80 miles up, burning as it entered the atmosphere. If anything did come down, it would have landed in the ocean."

Meteorite fragments have been found from Australia and Antarctica to the Sahara Desert and the Great Plains in the USA. Only a few hundred had been discovered by the beginning of the 20th century but there are now more than 30,000 in collections across the globe.

The effect of larger meteorite impacts – especially those made by iron meteorites – are responsible for a number of famous craters, including Barringer Meteorite Crater in Arizona, Odessa Meteor Crater in Texas, the Wabar Craters in Saudi Arabia, and Wolfe Creek Crater in Western Australia.


quarta-feira, 19 de setembro de 2012

Largest moon rock ever auctioned could fetch $380,000

A moon rock for sale by Heritage Auctions came to Earth as a meteorite. The specimen is expected to sell for upwards of $380,000. (Heritage Auctions)

If you have some serious cash lying around, a chunk of the moon could be yours.
A piece of lunar meteorite is on sale at auction, and experts estimate the final price will tally at keast $340,000. The rock, called Dar al Gani 1058, is the largest piece of the moon ever to be auctioned, according to Heritage Auctions, which is handling the sale.
The 4-pound (1815 grams) meteorite is also the fourth-largest chunk of the moon available to the public, since the moon rocks collected by Apollo astronauts were never put up for sale.
"When it comes to the market for moon rocks, size does matter — but so does origin," said Robert Pearlman, editor of space history and artifacts site, a partner and contributor.
Moon rocks retrieved by human-made robotic probes, such as those sent by the United States and the Soviet Union, fetch higher prices than lunar meteorites, because collectors value the history they represent, he said.
"For example, three seed-sized pieces of the moon that were brought back to Earth by a Russian robotic probe in 1970 were sold at auction 30 years later for $442,500," Pearlman told "And while the moon rocks recovered by the Apollo astronauts are considered National Treasures and have never been awarded to individuals, hypothetical appraisals have suggested even a 1-gram sample could be worth millions."
The slab-shape Dar al Gani 1058 came to Earth via natural forces, originating as a piece of lunar highland breccias from the moon's far side, experts say. Scientists don't know exactly when it was dislodged from the moon and fell onto Earth, but it was found in Libya in 1998, according to the Meteoritical Society. It was put up for auction by an anonymous collector.
The opening bid for the moon rock is $170,000, and the auction ends Oct. 14. Heritage Auctions calls the specimen "worthy of the most important natural history museums in the world."
While the rock is expected to go to a museum, a private buyer could also be the highest bidder.


terça-feira, 18 de setembro de 2012

Old asteroid crater in eastern Siberia is full of diamonds

'Trillions of carats' lie below a 35-million-year-old, 62-mile diameter asteroid crater in eastern Siberia known as Popigai Astroblem. The Russians have known about the site since the 1970s.

Russia has just declassified news that will shake world gem markets to their core: the discovery of a vast new diamond field containing "trillions of carats," enough to supply global markets for another 3,000 years.

The Soviets discovered the bonanza back in the 1970s beneath a 35-million-year-old, 62-mile diameter asteroid crater in eastern Siberia known as Popigai Astroblem.

They decided to keep it secret, and not to exploit it, apparently because the USSR's huge diamond operations at Mirny, in Yakutia, were already producing immense profits in what was then a tightly controlled world market.

How much do you know about Russia? Take our quiz.

The Soviets were also producing a range of artificial diamonds for industry, into which they had invested heavily.

The veil of secrecy was finally lifted over the weekend, and Moscow permitted scientists from the nearby Novosibirsk Institute of Geology and Mineralogy to talk about it with Russian journalists.

According to the official news agency, ITAR-Tass, the diamonds at Popigai are "twice as hard" as the usual gemstones, making them ideal for industrial and scientific uses.

The institute's director, Nikolai Pokhilenko, told the agency that news of what's in the new field could be enough to "overturn" global diamond markets.

"The resources of super-hard diamonds contained in rocks of the Popigai crypto-explosion structure, are by a factor of ten bigger than the world's all known reserves," Mr. Pokhilenko said. "We are speaking about trillions of carats. By comparison, present-day known reserves in Yakutia are estimated at one billion carats."

The type of stones at Popigai are known as "impact diamonds," which theoretically result when something like a meteor plows into an existing diamond deposit at high velocity. The Russians say most such diamonds found in the past have been "space diamonds" of extraterrestrial origin found in meteor craters.

They claim the Popigai site is unique in the world, thus making Russia the monopoly proprietor of a resource that's likely to become increasingly important in high-precision scientific and industrial processes.

"The value of impact diamonds is added by their unusual abrasive features and large grain size," Pokhilenko told Tass. "This expands significantly the scope of their industrial use and makes them more valuable for industrial purposes."

Russian scientists say the news is likely to change the shape of global diamond markets, although the main customers for the super-hard gems will probably be big corporations and scientific institutes.


segunda-feira, 17 de setembro de 2012

Did the Reign of Dinosaurs Begin, as Well as End, with a Meteorite Strike?

Western New Jersey holds one of the most visible examples of the Triassic–Jurassic boundary, where evidence could settle the debate about what caused a mega-extinction event that paved the way for the age of dinosaurs

A huge meteorite strike may have helped the dinosaurs rise as well as fall. That's what a small crew of mud-spattered researchers who drilled down hundreds of feet in New Jersey this summer wanted to discover.

Roughly 200 million years ago, at least half the species on Earth died off over the course of about 100,000 years, both on land and in sea. This mass extinction, at the boundary between the Triassic and Jurassic periods and one of five known such events in Earth's geologic history, set the stage for dinosaurs to rise to prominence and dominate the planet's terrestrial life for the next 135 million years.

The quest for answers regarding dinosaurs and the end-Triassic mass extinction had previously led paleontologist Paul Olsen and his colleagues at Columbia University's Lamont –Doherty Earth Observatory (LDEO) to globe-trot to around cities in Morocco and along sea cliffs in the U.K . digging up clues from that past era. This summer, it brought them to the Kell family's yard in western New Jersey—the area holds one of the most visible examples of the Triassic– Jurassic boundary.

The sub surface dig for revealing sediment cores required a lightweight, portable drill called a Winkie. D iamond-tipped and gas-powered , it can be carried and operated by only two people—often paleomagnetist Dennis Kent and geochemist Morgan Schaller, both at Rutgers University. The goal was to unearth evidence of what might have triggered the mass extinction.

"The dinosaurs had actually first evolved about 25 million years before the mass extinction, but after their competition got wiped out, it looks like they came in like gangbusters," Olsen says. Such competition included extinct relatives of modern crocodilians, such as the large and carnivorous land-based rauisuchians and semiaquatic phytosaurs as well as  plant-eating aetosaurs and revueltosaurs.

Many scientists blame the end-Triassic mass extinction on exceptionally massive volcanic eruptions over the course of less than 20,000 years that occurred about when the one-time supercontinent of Pangea began rifting apart. These eruptions coated what was to become Africa and the Americas with a million cubic kilometers of lava and doubled the level of carbon dioxide in the air causing massive global warming, "about a 3- degree Celsius increase on average in temperature, if the climate system was as sensitive as models suggest," Olsen says, citing research published by Schaller, Kent and their colleague James Wright in 2011.

Those 3 degrees "could have translated to lethally high summer temperatures, especially for some kinds of broad-leafed vegetation, which in turn could have led to extinctions of animals dependent on the plants," Olsen explains. "In the oceans, a rapid rise in carbon dioxide would have resulted in acidifying the oceans and badly impacting animals that make calcium carbonate skeletons, such as corals, bivalves and ammonites, all of which suffered massive drops in diversity."

Volcanic eruptions also release large amounts of sulfur-laden compounds that reflect sunlight, however, causing cooling. "The cooling only lasts a short time because the sulfur is removed quickly from the atmosphere, but the effect can be very intense, and for a world in which there were no ice caps and there were forests at the poles, such dramatic drops in temperature cold have been devastating on land," Olsen says.

"One can envision the carbon dioxide raising temperatures multiple times for tens of thousands of years, fading away over 100,000 years or so, but these periods of great warmth would be punctuated by many intervals of abrupt and intense cooling caused by the sulfur," Olsen continues. "This one-two punch may have been too much for terrestrial ecosystems and the warmth and acidity in the oceans too much for marine life. Result: mass extinction."


terça-feira, 11 de setembro de 2012

On display for the first time in 30,000 years: Britain's biggest meteorite, weighing 200lb, enters museum after 80 years as family heirloom

On display for the first time in 30,000 years: Britain's biggest meteorite, weighing 200lb, enters museum after 80 years as family heirloom

Rock was 'used by Druids in a burial mound' before being excavated by an archaeologist 200 years ago, researchers believe
The 200lb space rock is four times larger than the next biggest discovered

The biggest meteorite to ever fall to Britain has gone on display for the first time.
The rock lay undiscovered on the doorstep of a house for at least 80 years before being revealed as a 200lb space rock, measuring 1.6ft long.
After sitting on the step of Lake House near Wilsford-cum-Lake, Wiltshire, since the 1900s, it is on display for the first time at the Salisbury and South Wiltshire Museum from today.

Prof Colin Pillinger with the rock, now on display for the first time in 30,000 years

Experts there initially believed the meteorite had landed in another part of the world several thousand years ago before being brought over to England.
But researchers worked out that the rock had actually landed here 32,000 years ago - making it bigger than any other meteorite found in Britain.
It was handed in to the Natural History Museum when the Bailey family sold Lake House to musician Sting in 1991.
Professor Colin Pillinger, said he realised the meteorite's amazing history when he spotted a photograph of it in Country Life magazine.
He said: 'We know that it fell onto this part of the world around 30,000BC, and it probably would have fallen onto an ice sheet, which preserved it.
'We think it must have been found by Neolithic people who built Stonehenge and all the hundreds of burial barrows all over Salisbury Plain.

Direct to the door step from space: Experts previously assumed that the rock landed in another part of the world before being brought over to England

'They buried it, which preserved it again, in the chalk, because meteorites don't tend to last long in the British climate.
'It was when we realised from photos in Country Life, that this stone had been at Lake House before the Baileys and going back into the 19th century that we realised it must have been dug up by Edward Duke, whose family lived there for 11 generations, who was a trained archaeologist and who excavated lots of barrows on his estate.
'It was a real mystery that needed a lot of detective work. That's the great thing about science, that you start off with one thing and then end up with a different story altogether.'

The significance of the rock first became apparent in 1991 when the family of the previous owner of Lake House decided to sell the property.
They took the specimen - which they called 'grandfather's meteorite' - to the Natural History Museum but experts could not verify if it had been found in the UK.
The family had always assumed that their grandfather had collected the rock on his travels abroad.

Stately: Lake House, near Wilsford-cum-Lake, Wiltshire, where the rock sat on the doorstep for 80 years

But Professor Pillinger, who has been researching the meteorite's history for more than a year, found photographic evidence of the rock on the steps of the house before the family owned it.
The expert, famed for his work on the Beagle II Mars explorer, believes the rock could have landed on Salisbury Plain 30,000 years ago before being picked up by druids.
They might have used it in the construction of a chalk mound - such as Silbury Hill near Avebury, Wilts., - which would have protected it from decay, he explained.
The meteorite, known as a common chondrite, went on display at the Salisbury and South Wiltshire museum, in the city, on Tuesday.
Adrian Green, director of the museum, said: 'It's not uncommon for exotic rocks to be built into burial mounds.
'And it's still covered in chalk which is the bedrock of the landscape.
'And it's colossal - it would take four people to lift it - and it's not aesthetically pleasing, so common sense dictates that this has not been shipped from abroad at ridiculous cost and significant effort, but that it came from the UK.'
The meteorite is on long-term loan to the museum from the Bailey family and will be displayed there until September 22.