domingo, 24 de fevereiro de 2013
The Only Woman Who Ever Got Hit By A Meteorite Survived
Imagine going about your day like the people in Russia only to be smacked against a wall by a meteorite’s shockwave. That’s already crazy. But imaging being in your home, napping on your couch and actually getting hit by an actual meteorite. That actually happened to Ann Hodges in 1954. She survived.
In the only confirmed account of a person getting struck by a meteorite, Ann Hodges was left with just a large bruise after the softball-sized meteorite broke through her ceiling and bounced off a radio before it thumped her on her thigh. After all of the people who have ever lived in this world and after all the meteorites that have hit Earth, she’s the only one to have ever been hit. Amazing.
It’s especially funny to look back in time. Most people said the meteorite, which hit Hodges in Sylacauga, Alabama, was like “a fireball, like a gigantic welding arc” but others assumed it was the work of the Soviets. After it was confirmed to be a meteorite, there was a big hodgepodge over who actually owned the meteorite.
Hodges eventually gained possession of the meteorite and though she survived being struck by the space rock in 1954, she passed away in 1972 at the age of 52 because of kidney failure. [National Geographic]
Source: http://www.gizmodo.com.au/
sábado, 23 de fevereiro de 2013
Russian meteorite hunters search for bit of space history
While many people have been helping clean up the devastation caused by the meteor which came down in the Russian Urals last week, others have been searching the shores of Lake Chebarkul- which it is thought to have struck - for tiny fragments of the space rock.
Scientists and members of the public are looking for small holes in the snow that indicate fragments of meteorite below - which they plan to hold on to as keepsakes or sell on to collectors and researchers.
BBC Russian's Oleg Boldyrev reports.
segunda-feira, 18 de fevereiro de 2013
Meet one of the top Meteorite Hunters
Michael Farmer talks about the art of finding—and selling—space rocks.
Meteor hunter Michael Farmer looks for meteorite fragments in a Wisconsin cornfield.
Michael Farmer is one of the world's only full-time meteorite hunters. Since the 1990s, the 40-year-old Tucson, Arizona, resident has been scouring the world for pieces of interstellar rock, racing to be the first one on the scene and selling his finds to museums and private collectors. On Friday, as Russians reportedly scrambled to collect fragments from a passing meteorite that injured hundreds, Farmer spoke with National Geographic about his unusual line of work.
Why are so many people in Russia busy gathering up meteorite fragments?
It's a historic event. This will be talked about forever. Everyone wants to have a little piece of it. And scientifically, we want to study it. We want to know what's out there, and we want to know how big it is, and we want to know what damage it can cause. The preliminary data from NASA's Jet Propulsion Laboratory says about 7,000 tons landed.
How many meteorite fragments are known to be on Earth?
There are a couple of hundred thousand known meteorites. Of course, there's millions and millions on the planet; we just have to find them. Most of the Earth is inhospitable—heavy forest, jungle, ocean. Meteorites that fall in the ocean are just gone, disappeared to the bottom.
How many other full-time meteorite hunters are there?
Dedicated, serious meteorite hunters? There are maybe 20 of us. If you add in the part-timers who go somewhere whenever [an impact is] close to them, then you might approach a hundred.
How did you become a meteorite hunter?
Here in Tucson right now we have the world's biggest mineral show going on. I bought a meteorite at this very same show 20 years ago, and I was absolutely obsessed and hooked. Since then I've been around the world more times than I can count—four million miles on American Airlines alone.
How many countries have you been to?
About 70 countries, by my last count. About 50, 59 trips to Africa—a lot of work in Africa. The Sahara and other deserts there make meteorites easier to find than on other terrains, and also keep them well preserved.
What are the challenges you face when you're on a hunt?
Well, you're usually going into a kind of chaotic scene where nobody really knows much. In Africa and other places I go [the locals] don't usually understand what's happening, and most of the time they don't care. They're more concerned with eating that day. But the instant some guy shows up and says, "I'll pay you to find this rock," the whole village empties—and then lots of rocks show up.
Related: Best Meteorites for Tourists
It can be dangerous work. I've been robbed, put into prison. For example, I was in prison two years ago in the Middle East, in Oman—actually sentenced, convicted, and put in prison for three months for "illegal mining activity." Not a very nice time. And the same year, 2011, in the fall I went to Kenya three times, after a major meteorite fell. On the third trip over I had a robbery where they ambushed us and almost murdered me. I was down on my knees, with a bag over my head and a machete on my throat and a gun at my head, being beaten. Luckily they decided to just take everything and leave instead of killing us. It's a dangerous line of work because it involves money, and people want that money.
What's the most valuable meteorite you've found?
Well, I've found three separate moon rocks in the Middle East. [Moon rocks are considered a type of meteorite that came loose from the lunar surface and fell to Earth.] And one of them I sold for $100,000 a week later. It was just a small piece—the size of a walnut. But the best meteorite I found was with my three partners up in Canada. It was actually discovered in 1931, but we went back to the location and discovered 53 kilograms [117 pounds] more. It's an extremely rare type of meteorite called a pallasite, and it's about 4.5 billion years old. We sold it to the Canadian government for just under a million dollars. Now it's in the Royal Ontario Museum, in Toronto, and it's considered a national treasure.
Where else do you sell your wares?
Well, I do shows around the world, in France, Germany, Japan. I go to expos, like this one here in Tucson, which is the biggest mineral show in the world and lasts for three weeks. And museums are always calling me.
Related: Archival Photos of Meteorite Recovery
It's a small market. It's not like I need a shop or anything. People call me or email me or go to my website and check it out. The market these days is so ravenous for anything new that when I get a new meteorite, it's usually sold in hours. I don't even have to work anymore. I just make phone calls to a few people, and it's all gone.
Where do you store your collection?
I have multiple storage sites—never put all your eggs in one basket. And I have lots of bulk material. Sometimes I buy this stuff by the ton, and it goes into storage and I sell it off one piece at a time.
What's the verification process like?
Any meteorite, anything that we want to have an official name, has to go to a laboratory, where it gets sectioned and studied by scientists. For example, I'd guess this meteorite in Russia yesterday will be in a lab in Moscow, being researched within hours.
Related: History's Big Meteorite Crashes
In the collector market, we work collaboratively with the scientists. I supply them with rocks, and they supply me with data, both of which I need to make money. People want to know what something is before they buy it.
Are there legal or ethical implications to meteorite hunting?
There always are. Certain countries have passed laws. But when I was arrested in Oman, they actually had no law—they were just very upset that we were taking lots of meteorites. The only law they could charge us with was illegal mining operations—basically running a company in the country without government licensing. But I won on appeal because we had no mining equipment. We were picking up rocks off the surface of the desert. And a judge said, "If a child could do it, then it's not mining." And I was immediately released and sent home.
But there's always friction between the collecting market and the scientific market. There are scientists out there who believe that no meteorite should be in private hands. Well, I tell you, I've been on hunts all over the world and I've only run into scientists a couple of times. They don't have the time or money to do it. So if it wasn't for us, 99 percent of these meteorites would be lost to science.
What about this meteorite strike—do you think scientists will go to Russia?
I guarantee there'll be scientists from everywhere in the world going to this one.
Are you catching the next flight to Moscow?
Well, of course as a meteorite dealer, I want to own this. I woke up this morning to a hundred e-mails from people begging me to get on a plane and go get it so they can buy a piece.
But I'm probably not going. Getting into Russia can be complicated. I'll just buy some from the Russians when it comes out.
Of course, if this had happened in China or somewhere in Africa, I'd be packing my bags right now and getting on a plane, figuring it all out when I get there.
By: Jeremy Berlin
National Geographic News
Meteor hunter Michael Farmer looks for meteorite fragments in a Wisconsin cornfield.
Michael Farmer is one of the world's only full-time meteorite hunters. Since the 1990s, the 40-year-old Tucson, Arizona, resident has been scouring the world for pieces of interstellar rock, racing to be the first one on the scene and selling his finds to museums and private collectors. On Friday, as Russians reportedly scrambled to collect fragments from a passing meteorite that injured hundreds, Farmer spoke with National Geographic about his unusual line of work.
Why are so many people in Russia busy gathering up meteorite fragments?
It's a historic event. This will be talked about forever. Everyone wants to have a little piece of it. And scientifically, we want to study it. We want to know what's out there, and we want to know how big it is, and we want to know what damage it can cause. The preliminary data from NASA's Jet Propulsion Laboratory says about 7,000 tons landed.
How many meteorite fragments are known to be on Earth?
There are a couple of hundred thousand known meteorites. Of course, there's millions and millions on the planet; we just have to find them. Most of the Earth is inhospitable—heavy forest, jungle, ocean. Meteorites that fall in the ocean are just gone, disappeared to the bottom.
How many other full-time meteorite hunters are there?
Dedicated, serious meteorite hunters? There are maybe 20 of us. If you add in the part-timers who go somewhere whenever [an impact is] close to them, then you might approach a hundred.
How did you become a meteorite hunter?
Here in Tucson right now we have the world's biggest mineral show going on. I bought a meteorite at this very same show 20 years ago, and I was absolutely obsessed and hooked. Since then I've been around the world more times than I can count—four million miles on American Airlines alone.
How many countries have you been to?
About 70 countries, by my last count. About 50, 59 trips to Africa—a lot of work in Africa. The Sahara and other deserts there make meteorites easier to find than on other terrains, and also keep them well preserved.
What are the challenges you face when you're on a hunt?
Well, you're usually going into a kind of chaotic scene where nobody really knows much. In Africa and other places I go [the locals] don't usually understand what's happening, and most of the time they don't care. They're more concerned with eating that day. But the instant some guy shows up and says, "I'll pay you to find this rock," the whole village empties—and then lots of rocks show up.
Related: Best Meteorites for Tourists
It can be dangerous work. I've been robbed, put into prison. For example, I was in prison two years ago in the Middle East, in Oman—actually sentenced, convicted, and put in prison for three months for "illegal mining activity." Not a very nice time. And the same year, 2011, in the fall I went to Kenya three times, after a major meteorite fell. On the third trip over I had a robbery where they ambushed us and almost murdered me. I was down on my knees, with a bag over my head and a machete on my throat and a gun at my head, being beaten. Luckily they decided to just take everything and leave instead of killing us. It's a dangerous line of work because it involves money, and people want that money.
What's the most valuable meteorite you've found?
Well, I've found three separate moon rocks in the Middle East. [Moon rocks are considered a type of meteorite that came loose from the lunar surface and fell to Earth.] And one of them I sold for $100,000 a week later. It was just a small piece—the size of a walnut. But the best meteorite I found was with my three partners up in Canada. It was actually discovered in 1931, but we went back to the location and discovered 53 kilograms [117 pounds] more. It's an extremely rare type of meteorite called a pallasite, and it's about 4.5 billion years old. We sold it to the Canadian government for just under a million dollars. Now it's in the Royal Ontario Museum, in Toronto, and it's considered a national treasure.
Where else do you sell your wares?
Well, I do shows around the world, in France, Germany, Japan. I go to expos, like this one here in Tucson, which is the biggest mineral show in the world and lasts for three weeks. And museums are always calling me.
Related: Archival Photos of Meteorite Recovery
It's a small market. It's not like I need a shop or anything. People call me or email me or go to my website and check it out. The market these days is so ravenous for anything new that when I get a new meteorite, it's usually sold in hours. I don't even have to work anymore. I just make phone calls to a few people, and it's all gone.
Where do you store your collection?
I have multiple storage sites—never put all your eggs in one basket. And I have lots of bulk material. Sometimes I buy this stuff by the ton, and it goes into storage and I sell it off one piece at a time.
What's the verification process like?
Any meteorite, anything that we want to have an official name, has to go to a laboratory, where it gets sectioned and studied by scientists. For example, I'd guess this meteorite in Russia yesterday will be in a lab in Moscow, being researched within hours.
Related: History's Big Meteorite Crashes
In the collector market, we work collaboratively with the scientists. I supply them with rocks, and they supply me with data, both of which I need to make money. People want to know what something is before they buy it.
Are there legal or ethical implications to meteorite hunting?
There always are. Certain countries have passed laws. But when I was arrested in Oman, they actually had no law—they were just very upset that we were taking lots of meteorites. The only law they could charge us with was illegal mining operations—basically running a company in the country without government licensing. But I won on appeal because we had no mining equipment. We were picking up rocks off the surface of the desert. And a judge said, "If a child could do it, then it's not mining." And I was immediately released and sent home.
But there's always friction between the collecting market and the scientific market. There are scientists out there who believe that no meteorite should be in private hands. Well, I tell you, I've been on hunts all over the world and I've only run into scientists a couple of times. They don't have the time or money to do it. So if it wasn't for us, 99 percent of these meteorites would be lost to science.
What about this meteorite strike—do you think scientists will go to Russia?
I guarantee there'll be scientists from everywhere in the world going to this one.
Are you catching the next flight to Moscow?
Well, of course as a meteorite dealer, I want to own this. I woke up this morning to a hundred e-mails from people begging me to get on a plane and go get it so they can buy a piece.
But I'm probably not going. Getting into Russia can be complicated. I'll just buy some from the Russians when it comes out.
Of course, if this had happened in China or somewhere in Africa, I'd be packing my bags right now and getting on a plane, figuring it all out when I get there.
By: Jeremy Berlin
National Geographic News
sexta-feira, 15 de fevereiro de 2013
Meteor Explosion in Russia Hurts More than 900 People: Reports
More than 500 people are reportedly injured, and hundreds of buildings damaged, after a meteorite streaked across the sky above Russia's Ural Mountains Friday morning (Feb. 15) and exploded in a massive blast.
The meteor explosion was centered around the Chelyabinsk region, which is about 930 miles (1,500 kilometers) east of Moscow.
Most of the hundreds injured were reportedly hurt by falling glass in the blast, 112 of whom have been hospitalized, due to cuts from the shattered glass resulting from the blast. In addition, an estimated 297 buildings were damaged, including six hospitals and 12 schools, according to translations of updates by the Russian Emergency Ministry.
Scientists think a meteoroid entered the atmosphere above Russia's southern Chelyabinsk region, where it exploded and broke up into meteorites scattered across three regions of Russia and Kazakhstan, according to news reports. [Photos of Russia's Meteor Fireball Blast]
"I would think that this is likely an exploding fireball (or bolide) event caused by the atmospheric impact of a small asteroid," Don Yeomans, head of NASA's Near-Earth Object Program, told SPACE.com. "If the reports of ground damage can be verified, it might suggest an object whose original size was several meters in extent before entering the atmosphere, fragmenting and exploding due to the unequal pressure on the leading side vs. the trailing side."
Basically, Yeomans added, the meteor "pancaked and exploded."
(A bolide is an extraterrestrial body ranging in size from 0.6 to 6 miles, or 1-10 km across that hits Earth at velocities faster than a speeding bullet, according to the U.S. Geological Survey.)
"This bolide event probably had nothing to do with the upcoming close Earth approach of asteroid 2012 DA14, which is due to pass closely (and safely) past the Earth at 19:24 GMT today," or 2:24 p.m. ET, Yeomans wrote, adding that the Russian bolide trail did not travel south to north as the asteroid will.
"And the separation in time between the fireball and 2012 DA14 close approach is significant," Yeomans said.
A large chunk of the space rock has reportedly been discovered in a lake in the Chelyabinsk region, CNN reports.
A report by the Russian television news agency Russia Today showed video of the meteor, which included what appears to be a fireball streaking across the sky from several vantage points. At times the object is so bright it casts shadows.
In 1908, a fireball exploded over the Tunguska River in Siberia, Russia, flattening hundreds of square miles of land during a massive blast. That fireball was created by the explosion of an object about 150 feet (45 meters) across, NASA scientists have said.
A similarly sized object, the asteroid 2012 DA14, will fly extremely close to Earth on Friday, but will not hit the planet. The asteroid will approach within 17,200 miles (27,000 kilometers) of the Earth —about 5,000 miles (8,046 km) closer than geosynchronous satellites —during the close shave.
Asteroid 2012 DA14 was discovered in February 2012 and is being closely tracked by NASA and astronomers around the world. The asteroid is about half the size of a football field, but will not be visible to the naked eye when it flies by on Friday. A small telescope or binoculars, very dark skies and good timing will be needed to see the fast-moving asteroid.
Bounty sets off hunt for meteorite pieces (so far none have been found)
THE Russian city where the biggest meteorite to hit earth in more than 100 years crashed last week is facing a gold rush, with collectors offering more than $15,000 for a fragment of the rock.
A day after the fireball streaked across the sky and exploded with the force of an atomic bomb, residents in Chelyabinsk were out in force searching for pieces to sell. Potential buyers posted messages on the Russian internet calling on finders to come forward. One Russian buyer offered 500,000 roubles ($16,000) for a single fragment.
The gold rush begins for fragments of Russian meteor worth more than £10,000 each as astronomers warn UK had a lucky escape
'Meteor hunters' are out in force as collectors offer large sums
But they may have to wait for spring for snow to thaw to search
Astronomers say meteor could have hit UK if the it struck at a different time
The meteor that crashed in central Russia on Friday has sparked a modern-day gold rush as treasure hunters flock to the area for fragments worth more than £10,000.
Just a day after the 40-tonne meteor, which injured more than 1,200 people with flying fragments of glass and rubble, hurtled across the sky above Chelyabinsk, locals were out in force seeking fragments to sell to collectors desperate for a piece of the celestial body.
Enthusiasts took to the internet to let locals with a fragment know they could make big money. One Russian buyer was offering 500,000 roubles (£10,700) for a single rock.
Locals searching for meteorite fragments have gathered at a frozen lake where a chunk of meteorite hit. Collectors are offering £10,000 for a single piece
Meanwhile, experts say the meteor could have hit a UK city with the force of a nuclear bomb if it had entered the atmosphere at a different time of day.
The meteor penetrated Earth's atmosphere at a speed of at least 33,0000mph.
As it raced through the sky, the 50-foot wide chunk of space rock compressed the air ahead of it, creating the enormous temperatures that meant it exploded in a fireball somewhere between 18 and 32 miles above the ground at around 9.20am local time on Friday.
Although some debris fell to earth, ‘whipping up a pillar of ice, water and steam’ and creating a 20-foot-wide crater, the damage in nearby towns was actually caused by shockwaves created by the meteor breaking the sound barrier and then exploding.
Shockwave: People heading to work in Chelyabinsk, Russia, heard what sounded like an explosion, saw a bright light and then felt a shockwave when a meteor soared across the sky above them
The focus of the meteor hunters' efforts was a frozen reservoir outside the nearby town of Chebarkul, where the largest meteorite pieces are thought to have crashed, reports The Sunday Times.
Russian authorities stopped a group of locals searching around a hole in the ice as they want people to stay away from the fragments until scientists from Moscow have tested them. Russian authorities also said the search for the meteorite may have to wait until spring when the region's ice and snow thaws.
'The web is awash with people saying they want to buy this stuff," said Oleg Karpov, a Chelyabinsk local. 'Maybe this thing was not that bad after all if a few of us make some money out of it.'
Collectors from around the world will be keen to get hold of a piece. Film director Steven Spielberg is a noted collector. In October a 9in piece of the Seymchan meteorite found in Siberia in 1960 sold in New York for $43,750 (£28,200).
Astronomers have also revealed that the meteor could have hit UK cities if it had hit at a slightly different time of day.
Nasa said that when the meteor entered the atmosphere, it exploded with the force of a nuclear weapon.
The revelation, based on an analysis of the earth's rotation, comes as scientists reveal that they are planning a state-of-the-art detection system to give warning of incoming asteroids and meteorites, reports the Observer.
The announcement of the decision to build the Asteroid Terrestrial-Impact Last Alert System, or Atlas, on Hawaii was made following the meteorite crash in Russia.
If the meteorite had hit at a different time of day, it could have struck the UK with devastating consequences
quarta-feira, 13 de fevereiro de 2013
Earth-buzzing asteroid worth $195 billion, space miners say
The space rock set to give Earth a historically close shave this Friday, Feb. 15, may be worth nearly $200 billion, prospective asteroid miners say.
The 150-foot-wide asteroid 2012 DA14 — which will zoom within 17,200 miles of Earth on Friday, marking the closest approach by such a large space rock that astronomers have ever known about in advance — may harbor $65 billion of recoverable water and $130 billion in metals, say officials with celestial mining firm Deep Space Industries.
That's just a guess, they stressed, since 2012 DA14's composition is not well known and its size is an estimate based on the asteroid's brightness.
The company has no plans to go after 2012 DA14; the asteroid's orbit is highly tilted relative to Earth, making it too difficult to chase down. But the space rock's close flyby serves to illustrate the wealth of asteroid resources just waiting to be extracted and used, Deep Space officials said. [Deep Space Industries' Asteroid-Mining Vision in Photos]
"While this week's visitor isn't going the right way for us to harvest it, there will be others that are, and we want to be ready when they arrive," Deep Space chairman Rick Tumlinson said in a statement Tuesday.
Deep Space Industries wants to use asteroid resources to help humanity expand its footprint out into the solar system. The company plans to convert space rock water into rocket fuel, which would be used to top up the tanks of off-Earth satellites and spaceships cheaply and efficiently.
Asteroidal metals such as iron and nickel, for their part, would form the basis of a space-based manufacturing industry that could build spaceships, human habitats and other structures off the planet.
The idea is to dramatically reduce the amount of material that needs to be launched from Earth, since it currently costs at least $10 million to send 1 ton of material to high-Earth orbit, officials said.
"Getting these supplies to serve communications satellites and coming crewed missions to Mars from in-space sources like asteroids is key if we are going to explore and settle space," Tumlinson said.
Deep Space Industries is just one of two asteroid-mining firms that have revealed their existence and intentions in the past 10 months. The other is Planetary Resources, which has financial backing from billionaires such as Google execs Larry Page and Eric Schmidt.
Deep Space aims to launch a phalanx of small, robotic prospecting probes called Fireflies in 2015. Sample-return missions to potential targets would occur shortly thereafter, with space mining operations possibly beginning around 2020.
Planetary Resources also hopes its activities open the solar system up for further and more efficient exploration. The company may launch its first low-cost prospecting space telescopes within the next year or so.
Source: foxnews.com
quinta-feira, 7 de fevereiro de 2013
A Possible Naked-eye Comet in March
Feb. 6, 2013: Far beyond the orbits of Neptune and Pluto, where the
sun is a pinprick of light not much brighter than other stars, a vast
swarm of icy bodies circles the solar system. Astronomers call it the
"Oort Cloud," and it is the source of some of history's finest comets.
One of them could be heading our way now.
Comet Pan-STARRS was discovered by the Panoramic Survey Telescope &
Rapid Response System atop the Haleakala volcano in Hawaii. Astronomers
use the massive 1.8 meter telescope to scan the heavens for
Earth-approaching objects, both asteroids and comets, that might pose a
danger to our planet. In June 2011 a comet appeared, and it was named
"Pan-STARRS" after the acronym for the telescope.
In early March, the comet will pass about 100 million miles from Earth
as it briefly dips inside the orbit of Mercury. Most experts expect it
to become a naked-eye object about as bright as the stars of the Big
Dipper.
"But" says Karl Battams of the Naval Research Lab, "prepare to be
surprised. A new comet from the Oort Cloud is always an unknown quantity
equally capable of spectacular displays or dismal failures."
The Oort cloud is named after the 20th-century Dutch astronomer Jan
Oort, who argued that such a cloud must exist to account for all the
"fresh" comets that fall through the inner solar system. Unaltered by
warmth and sunlight, the distant comets of the Oort cloud are like time
capsules, harboring frozen gases and primitive, dusty material drawn
from the original solar nebula 4.5 billion years ago. When these comets
occasionally fall toward the sun, they bring their virgin ices with them.
Because this is Comet Pan-STARRS first visit, it has never been tested
by the fierce heat and gravitational pull of the sun. "Almost anything
could happen," says Battams. On one hand, the comet could fall apart--a
fizzling disappointment. On the other hand, fresh veins of frozen
material could open up to spew garish jets of gas and dust into the
night sky.
"Because of its small distance from the sun, Pan-STARRS should be very
active, producing a lot of dust and therefore a nice dust tail,"
predicts Matthew Knight of the Lowell Observatory.
"However," he cautions, "it could still be difficult to see. From our
point of view on Earth, the comet will be very close to the sun. This
means that it is only observable in twilight when the sky is not fully
dark."
The best dates to look may be March 12th and 13th when Pan-STARRS
emerges in the western sunset sky not far from the crescent Moon. A
comet and the Moon, together, framed by twilight-blue is a rare sight.
"My guess is that the primary feature visible to the naked eye will be
the gaseous coma around the head of the comet," says Knight. "The
comet's tail will probably require binoculars or a small telescope."
Two other key dates are March 5th when the comet comes closest to Earth
(about 100 million miles away) and March 10th, when the comet comes
closest to the sun. The dose of solar heating it receives just inside
the orbit of Mercury could be just what the comet needs to push it into
the realm of naked-eye visibility.
Comet Pan-STARRS should not be confused with another, even better comet
coming later this year. In Nov. 2013, Comet ISON could shine as
brightly as a full Moon in broad daylight when it passes through the
atmosphere of the sun: video <http://www.youtube.com/watch?v=5_1HdOCOJ_Q>.
"Two bright comets in one year is a rare treat," says Battams. "This
could be good."
Author: Dr. Tony Phillips
Production editor: Dr. Tony Phillips
Credit: NASA Science News
quarta-feira, 6 de fevereiro de 2013
Greenish rock may be first meteorite from Mercury
Pieces of the Moon and Mars have been found on Earth before, as well as chunks of Vesta and other asteroids — but what about the innermost planet, Mercury? That’s where some researchers think this greenish meteorite may have originated, based on its curious composition and the most recent data from NASA’s Messenger spacecraft.
NWA 7325 is the name for a meteorite fall that was spotted in southern Morocco in 2012, comprising 35 fragments totaling about 345 grams. The dark green stones were purchased by meteorite dealer Stefan Ralew, who operates the retail site SR Meteorites. Ralew immediately made note of the rocks' deep colors and lustrous, glassy exteriors.
Ralew sent samples of NWA 7325 to researcher Anthony Irving of the University of Washington, a specialist in meteorites of planetary origin. Irving found that the fragments contained surprisingly little iron but considerable amounts of magnesium, aluminum and calcium silicates — in line with what’s been observed by Messenger in the surface crust of Mercury.
Even though the ratio of calcium silicates is higher than what’s found on Mercury today, Irving speculates that the fragments of NWA 7325 could have come from a deeper part of Mercury’s crust, excavated by a powerful impact event and launched into space, eventually finding their way to Earth.
In addition, exposure to solar radiation for an unknown period of time and shock from its formation could have altered the meteorite’s composition somewhat, making it not exactly match up with measurements from Messenger. If this is indeed a piece of our solar system’s innermost planet, it will be the first Mercury meteorite ever confirmed.
But the only way to know for sure, according to a research paper written by Irving and his colleagues, is to conduct further studies on the fragments and, ultimately, samples that are returned from Mercury.
Irving’s team’s findings on NWA 7325 will be presented at the 44th Lunar and Planetary Science Conference, to be held in Houston from March 18 to 22. Read more in this Sky & Telescope article by Kelly Beatty.
Source: http://www.nbcnews.com
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