quarta-feira, 28 de novembro de 2012

Mysterious space object in Central Highlands skies solved

The suspicious cloud of smoke which appeared in the sky on Monday is said to have been a meteorite. Plenty of Australian locals witnessed the event.

A LOUD boom followed by a cloud of smoke in the sky had many Central Highlands Australia residents taking a closer look on Monday.







"Not very loud, but distinctive … if they come into the troposphere - which is the lower atmosphere - when they lose velocity, you might hear a series of booms."



Source: http://www.cqnews.com.au

Beyond 2012: Why the World Won't End in 2012. NASA scientists answer questions on the following 2012 topics:




Q: Does the Mayan calendar end in December 2012?

Q: Could planets align in a way that impacts Earth?
› More about alignment


- Don Yeomans, NASA senior research scientist


Q: What is the polar shift theory? Is it true that the Earth's crust does a 180-degree rotation around the core in a matter of days if not hours?
› More about polar shift


› Why you need not fear a supernova
› About super volcanoes

› Video: Solar Storms
› More about solar storms

Addition information concerning 2012 is available on the Web, at:
National Public Radio: "Ask A NASA Astrobiologist About Dec. 21 'Doomsday'"
NASA Astrobiology Institute: "Nibiru and Doomsday 2012"
Bad Astronomy: "The Planet X Saga: The Scientific Arguments in a Nutshell"
Sky and Telescope Magazine: "2012: The Great Scare"
Phys.org: "Mayan People Demand End to Doomsday Myth"
Houston Museum of Natural Science: "Maya 2012: Prophecy Becomes History"

You may participate in this FORUM (click here to join):  https://plus.google.com/events/ci7ak9p657rj34um819vadrm8jg

Source: http://www.nasa.gov

terça-feira, 27 de novembro de 2012

Former Sackville School scientist chosen for Christmas trip to Antarctica

A METEOROLOGIST has been guaranteed a white Christmas after she was accepted to participate in a science expedition in Antarctica.

Former Sackville School student Dr Katherine Joy will fly to the southern-most continent on Earth for the second successive year where she will hunt for meteorites that have crashed onto its frozen surface.

The mission, which has run since 1976, is funded by the US National Science Foundation and the Solar System Exploration division of NASA, and its findings will be submitted to the space agency to be studied.

Dr Joy said: "There are meteorites all over the world but as there is no rain in Antarctica they cannot be washed away, nor can their structures change. They are also a lot easier to find because they are black in the white snow.

"The most exciting discoveries are the meteorites from the Moon and Mars; they are the rarest that we find. Using snow mobiles, we go to different sites, or we go on foot to search through rocks.

"Depending on the weather we should spend eight hours a day out hunting for the meteorites and because we will be there during Antarctica's summer it will be light all the time.

"Our findings, which can vary from day to day, will then be stored and taken to NASA in Houston and the Smithsonian Institution in Washington to be analysed. We'll be studying to find out the usual things like the age, origin and how planets may have been formed. Meteorites can also give us an insight into planetary volcanoes."

Dr Joy will spend a total of two months in Antarctica with a team of between eight and twelve international planetary scientists and will also celebrate the New Year on the continent.

In December she flies to Christchurch, New Zealand, where the team will pick up some special clothing to combat the cold before flying in a ski-equipped plane to McMurdo Station, the largest base on Antarctica.

The meteorologist will return to Manchester University, where she works as a researcher, at the end of January while other scientists compile the expedition's findings.

She said: "I will spend a total of six weeks out camping with the team, which is more luxurious than it sounds, certainly more so than Scott and Shackleton experienced.

"We have power and food supplies.

"One of the positives is that I get to eat a lot of chocolate as we burn so many calories throughout the day.

"The team will spend Christmas Day exchanging presents with each other and last time I was on the trip I spent New Year's Eve watching a midnight sun, which was one the best memories I have."

To follow the expedition visit the team's blog

Source: http://www.thisissussex.co.uk

sábado, 24 de novembro de 2012

Study Suggests Earth, Mars Share Primordial Water Source, Chondritic Meteorites



nearly four months ago (Aug. 6).

On Earth, researchers from the Tokyo Institute of Technology, NASA's Johnson Space Center, the Lunar and Planetary Institute and the Carnegie Institution for Science drew their conclusions from the 79 gram Larkman Nunatak 06319 meteorite, which was recovered from Antartica in 2006, and the 82 gram Yamato 980459 Martian rock found in Antarctica in 1998, two of 62 rocks listed in NASA's Martian Meteorite Compendium.



"These meteorites contain trapped basaltic liquids, not unlike the basalts that erupt on Hawaii," John Jones, an experimental petrologist from NASA/Johnson, a study co-author and a member of the Curiosity science team, explained in a statement. "They are pristine samples that have sampled various Martian volatile element environments."





Source: www.aviationweek.com

sexta-feira, 16 de novembro de 2012

Rare, gem-studded meteorites were born in asteroid crashes

Solar system once may have been swarming with these tiny magnetic space rocks

Rare, gem-studded meteorites that resemble stained-glass windows when backlit may have come from magnetic asteroids that splintered apart in ancient collisions, scientists say.
The solar system once may have been full of swarms of these tiny magnetic asteroids, investigators add.
The space rocks known as pallasites, first discovered in 1794, are very rare, with only about 50 known. These meteorites are mixtures of iron-nickel metal and translucent, gem-quality crystals of the green mineral olivine.
"How you get a mixture of metal and these gem-like crystals has been a longstanding mystery," lead study author John Tarduno, a geophysicist at the University of Rochester in New York, told Space.com. "Because of the density differences of these materials, you'd normally think they'd separate into two different groups." [7 Strangest Asteroids Ever]
Chemical analyses have suggested the pallasites came from at least three different asteroids.
The researchers speculated that any magnetized material within these meteorites might shed light on their formation, since asteroids would possess magnetic fields only under certain special circumstances.
Magnetic meteorite mystery
The researchers looked at metal specks encapsulated within olivine crystals in two pallasites. These crystals are far better at recording past magnetic conditions than the surrounding metal is.

The investigators used a laser to heat the metal grains past their individual Curie temperatures — the point at which a metal loses its magnetization. The grains were then cooled in the presence of a magnetic field in order to become re-magnetized. By monitoring the grains using a highly sensitive measuring instrument called a SQUID ("superconducting quantum interference device"),  the research team was able to calculate the strength of the magnetic field that these metal particles once possessed.
The scientists found these metal specks were once strongly magnetized. This suggests the meteorites came from asteroids that were themselves once strongly magnetic, perhaps 4.2 billion to 4.4 billion years ago.

Earth's magnetic field is created by its dynamo, the churning in its molten metal core. Since asteroids are relatively small, they would have cooled quickly and no longer possess molten cores or magnetic dynamos. However, recent analyses suggest that Vesta, the second-largest asteroid in the solar system, once possessed a magnetic dynamo.
Ancient asteroid crashes
Past research had suggested that pallasites originate in the boundary layer between an asteroid's metallic core and rocky mantle, arising from the mixing of material one might find there. However, this would not explain the magnetization — if the pallasites formed this way, they would not have cooled sufficiently to become permanently magnetized before any dynamo in the asteroid decayed.
Instead, the research team's computer models suggested these magnetic pallasites formed when asteroids collided with much larger asteroids, protoplanet-sized bodies about 250 miles (400 kilometers) wide. The impact would have injected a liquid mix of iron and nickel from the cores of the smaller asteroids into the larger ones, explaining the jumble of materials seen within the meteorites. The pallasites would have formed while the dynamos of these protoplanets was still active.

"If pallasites really are made of metal from one object and minerals from another, then there might be chemical 'fingerprints' we can look for to prove this hypothesis," study author Francis Nimmo, a planetary scientist at the University of California, Santa Cruz, told Space.com. "Another critical measurement to make is to get the ages of the minerals. Our models predict particular age ranges for these minerals, which can be tested against age measurements."
Tarduno noted the meteorites they analyzed represent only one of the parent asteroids of pallasites. "We'd like to sample some of the others," he said. "The techniques we've used here can be applied to meteorites of other small bodies as well."
Past research suggests thousands of protoplanets at least 60 miles (100 km) wide once dwelt within the solar system. The new findings suggest many of these might have been magnetic.
"The more small bodies we study, the more dynamos we find," Nimmo said. "The problem is that we don't understand what is driving those dynamos. Did they operate like the Earth's dynamo, or are they driven another way — for example, by their iron cores sloshing around after a giant impact?"

Source: msnbc.msn.com

segunda-feira, 12 de novembro de 2012

Famous Mars Meteorite's 'Fossils': What Arctic Rocks Can Tell Us

ExoMars PanCam deployed on Commanche Spur analogue carbonates in lava breccia at Sverrefjell volcano on AMASE 2011. Left: Arnold Bauer, Joanneum Research, Austria; Right: Nicole Schmitz, German Aerospace Center (DLR).
CREDIT: Kjell Ove Storvik/AMASE 

In 1996, a research group led by Dave McKay of NASA’s Johnson Space Center claimed to have found evidence of fossilized life in a Mars meteorite known as Allan Hills 84001.

Not only did the shapes look like bacteria, but a form of magnetite (iron oxide) was found in the meteorite that, on Earth, is produced within the bodies of certain bacteria. The study also found tiny carbonate globules in the meteorite, which the scientists said were likely formed by living organisms in the presence of liquid water.

Since their surprising announcement, other scientists have closely examined the Allan Hills meteorite and concluded the microscopic shapes aren’t necessarily associated with life, and the different features in the meteorite all could have formed by non-biological processes.

Scientists studying the rocks of the arctic archipelago of Svalbard later found carbonate globule structures like those in the Allan Hills meteorite. Rather than being formed by life, the Svalbard structures formed when the Sverrefjell volcano erupted about a million years ago, forcing magma up through an overlying glacier. [5 Bold Claims of Alien Life]

A group at the Carnegie Institution of Washington used a Ramen spectrometer to compare abiotic Svalbard carbonate globules with those found in ALH 84001, and found a high degree of similarity.

Hans Amundsen runs the Mars analogue project AMASE (Arctic Mars Analogue Svalbard Expedition) and has been visiting Svalbard  every summer for the last decade to investigate the many ways it resembles Mars. Astrobiology Magazine editor Leslie Mullen recently sat down with him at the Third Conference on Terrestrial Mars Analogues in Marrakech, Morocco, to discuss what the Svalbard rocks tell us about the still-controversial Mars meteorite.

Q: Could you tell me about the rocks in Svalbard that are analogous with the ALH 84001 Mars meteorite?

Hans Amundsen: They have the same strange carbonate minerals as the Allan Hills meteorite.

Q: The same structures that were previously thought to be fossilized life?

Amundsen: Well, yes, McKay speculated that these spheres were some sort of indication of a bio-pattern or bio-shape. I don’t know anyone who still believes that. But the shapes we see in the Svalbard rocks are identical to the ones in the Allan Hills meteorite.

Q: Identical in shape, and chemically?

Amundsen: Both.

Q: I was at a meeting a few years ago where they were still debating whether the ALH 84001 features were biological.  One line of evidence they used to argue for life were the magnetic crystals they found in the meteorite.

Amundsen: Ok, yeah. The Allan Hills carbonates contain a particular type of iron oxide of magnetite with crystal morphologies that apparently are similar to what you find in microbes with these things. Some microbes use magnetite as a compass needle to navigate in the Earth’s magnetic field, so it knows when it’s swimming up and when it’s swimming down. But to my knowledge, those morphologies are not unique to bugs.

Q: Do you find them in rocks generally?

Amundsen: Not generally, but you find magnetites of all sorts of morphologies. I guess the basic point is that the McKay group had a set of observations that could be interpreted as biogenic in origin, but if you do your homework there are lots of different ways of interpreting those features. Like those carbonate spheres. If you deposit carbonate in still-standing water, it will form spheres. [7 Biggest Mysteries of Mars]

Q: In any environment?

Amundsen: It’s simply because the carbonate building blocks, they sort of migrate randomly in the liquid, and then suddenly one sticks. And once one has made a nucleus, the others will form on it and it will grow —it receives building blocks from around it and it just grows.

You know the gem called malachite? Malachite is an example of a very similar texture, where you have these cauliflower bulbous things. Malachite forms in the same way, in water with malachite building blocks, obviously, and it just nucleates and it forms a cauliflower accumulation, like the carbonates in the Allan Hills meteorite. Quite a few carbonates elsewhere form like that, from many different types of fluids.

Q: So could you describe the soils you were studying and how they formed?

Amundsen: They’re not really soils; it’s ice in rocks. In Svalbard, there were some volcanoes that erupted through a thick ice layer; it was maybe up to a kilometer thick. During that time it was extremely cold up there, more like Antarctica. So the volcanoes melted the ice and they became soaking wet.

At some stage you turn the heat off, the volcanic activity stops. And because it was still extremely cold, the wet volcanoes froze. By that time the glacial melt water that had been sitting in basalt acquired some of the magnesium and calcium from the basalt, and when it froze it had to get rid of its CO2 and calcium and magnesium and it made carbonates.

So it’s very similar to what happens with evaporites — you just keep removing water until your remaining fluid becomes so concentrated with whatever is left over that it starts to form minerals. And evaporation and freezing do pretty much the same thing — you simply remove H2O as vapor or ice.

Q: Was your study implying that Mars was never warm?

Amundsen: It doesn’t show that Mars was never warm, but it certainly indicates that you can make minerals like in the Allan Hills meteorite under low temperature conditions, possibly during freezing or close to zero degrees [Celsius]. A study published last year by a CalTech group found that the Allan Hills carbonates formed at about 20 degrees Celsius.

Q: Meaning they formed in that temperature.

Amundsen: Yeah. The Svalbard ones, we don’t know. But the oxygen isotopes suggests it was very cold.  But we can’t tell if it was zero or minus 30, because we don’t know the exact composition of the waters.

If you have the water and the carbonate that formed, you can estimate the temperature. But we only have the carbonate; the water is gone. But the only other carbonates on Earth that look similar to the Svalbard ones have formed during freezing of water in caves.

There’s examples from Arctic Canada and from Poland where there are these very unusual, very light oxygen isotopes. And the whole setting of the Svalbard volcanoes — they probably erupted under extremely cold climatic conditions, melted the ice and then froze again. So you can’t use the Allan Hills carbonates to argue for anything warm. But it was certainly wet. [Photos: The Search for Water on Mars]

Q: Volcanoes are warm, but I guess they are hot spots in a cold place.

Amundsen: Yeah, there’s been volcanism on Mars throughout its history, of course. But as a surface condition, you get essentially the same carbonates and sulfates forming under permafrost conditions as you do under tropical conditions. They don’t look different.

Q: And there’s nothing about the heat caused by being blasted off the surface that had anything to do with that?

Amundsen: No, I think there could be. The Allan Hills meteorite likely witnessed several blasts nearby before it was kicked out itself. So you could have had warm events triggered by impacts.

So you warm the top layer of the crust, and what maybe was permafrost then melted and froze back again. And we don’t know how deep the Alan Hills meteorite originally came from. Most people are thinking of it as sitting on the surface, but it could have been hundreds of meters subsurface, and was excavated by the impact.

You know from the shocked minerals from the Allan Hills meteorite that there were impacts going on. The age of the Hills meteorite was at a time when there were lots of impacts. But you can’t preclude that there was lukewarm water drizzling down from above.

Q: It’s all very interesting how the questions on the meteorite structures still aren’t completely settled.

Amundsen: In science there’s always a debate going on, but with the search for life on Mars I think it’s important to be conservative. If you can explain your observations with purely physical, abiotic processes, then you can’t use it to argue that you have found life outside Earth.


View the video:

Fonte: Space.com

quarta-feira, 7 de novembro de 2012

Claim of stolen meteorite worth $12 million goes to Yukon Appeal Court


Daniel Sabo is suing the federal government, staff members with the Geological Survey of Canada (GSC), and an RCMP officer claiming the meteorite he found in 1986 was replaced with a replica and he wants $12 million.

Scientists with the GSC concluded the growth on the space rock could be a natural result of oxidation of minerals, a salt-type crystal or a type of lichen.

The Yukon Supreme Court rejected Sabo's claim in a decision last year.

The case he presented to the court in 2010 claimed RCMP Corporal Dan Parlee failed to properly investigate, and that forensics expert Bill Schneck, who was hired by Sabo’s former lawyer, tampered with the rock without his permission.

Sabo, who represented himself before the appeal court panel on Monday, used photos showing the rock before and after it was returned to him.

He claimed a date stamp on one photo shows the GSC sliced into the rock before it had his permission to do so. He also said the agency obtained his permission only “under duress”.

Sabo said he found the rock while working on his mining claim near Mayo, Yukon.

An assaying company in B.C. agreed it was likely a meteorite, though the International Meteorite Society is the only group that can make such a certification

In 1998, Sabo noticed a green formation on the meteorite and tests showed the growth could be some kind of life form.

The rock was sent to the GSC in Ottawa to be analyzed and later polished with the small cut taken off for more detailed study.

Sabo has continually argued that the GSC kept his rock, replacing it with a replica.

While Sabo has estimated the rock’s value at $12.1 million, Alexander Benitah, who represents the Attorney General of Canada in the case, pointed to estimates that had was worth between $1,000 and $2,500 based on the evidence of the GSC.

Benitah also said Sabo’s valuation is based solely on the highest-priced meteorite found on the Internet.

He said there is simply no evidence to support Sabo’s claim and asked that the appeal be dismissed.

Justices Harvey Groberman, Christopher Hinkson and David Harris have reserved their decision on the matter.

Fonte: Whitehorse Star

quinta-feira, 1 de novembro de 2012

New 300 kilo meteorite found in POLAND


"We know the Earth's core is composed of iron, but we can't study it. Here we have a guest from outer space which is similar in structure and we can easily examine it," Professor Andrzej Muszynski told reporters in Poznan, western Poland, where the find was made public Wednesday.

"This can broaden our knowledge about the origins of the universe," the geologist said, quoted by the Polish PAP news agency.



"Until now, it's the largest find of its kind in this part of Europe," said Professor Wojciech Stankowski.

Fellow geologists at Adam Mickiewicz University in Poznan who are studying it believe the meteor crash-landed 5000 years ago and is composed mostly of iron with traces of nickel.

"It was like a gold rush, we became very excited. We didn't even bother to eat - we just kept on digging," Muszynski said of its hasty excavation.

Located just north of Poznan, the Morasko Meteorite Reserve boasts seven craters. The largest is nearly 100 metres in diameter and 11 metres deep. Scientists believe the site was formed 5000 years ago by meteors crashing into the Earth.

So far the Morasko reserve, marked by a shallow crater, has given up close to 1500 kilograms of smaller meteorites. Scientists now plan to broaden their hunt for meteorites in the region.

Fonte: http://technology.iafrica.com