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Noun(1) confusion resulting from failure to understand(2) something designed to mystify or bewilder(3) the activity of obscuring people's understanding, leaving them baffled or bewildered
1. bewilderment ::
6. puzzlement ::
English to Bengali Dictionary: mystification
Meaning and definitions of mystification, translation in Bengali language for mystification with similar and opposite words. Also find spoken pronunciation of mystification in Bengali and in English language.
Tags for the entry "mystification"
What mystification means in Bengali, mystification meaning in Bengali, mystification definition, examples and pronunciation of mystification in Bengali language.
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Astronomers have found a new, potentially habitable Earth-sized planet. It is one of two new planets discovered around the star Gliese 581, some 20 light years away. The planet, Gliese 581g, is located in a "habitable zone" -a distance from the star where the planet receives just the right amount of stellar energy to maintain liquid water at or near the planet's surface. The 11- year study, published in the Astrophysical Journal and posted online at arXiv.org, suggests that the fraction of stars in the Milky Way harboring potentially habitable planets could be greater than previously thought -as much as a few tens of percent.
- Potentially habitable planet discoveredWed, 29 Sep 2010, 17:30:56 EDT
- Newly discovered planet may be first truly habitable exoplanetFri, 1 Oct 2010, 10:43:53 EDT
- Newly discovered planet may be first truly habitable exoplanetWed, 29 Sep 2010, 17:30:58 EDT
- 15 new planets hint at 'traffic jam' of moons in habitable zoneMon, 7 Jan 2013, 10:33:00 EST
- Earth-like planets are right next doorWed, 6 Feb 2013, 11:35:11 EST
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MUNCIE, Ind. (AP) — More than a third of Indiana adults who consume alcohol say they regularly binge drink, a new Ball State University study found.
The U.S. Centers for Disease Control and Prevention defines binge drinking as men consuming five or more drinks or women consuming four or more drinks in about two hours. The CDC provided the data for Ball State's study.
Ball State researchers found that in 2011, about half of Indiana adults classified themselves as regular drinkers and nearly 35 percent of them said they binge drink, The Times of Munster reported (_URL_ ).
University researchers found that Indiana has the 32nd highest percentage of binge drinkers among the 50 states and the District of Columbia.
Adults 22 to 25 years old are more likely to binge drink and drink heavily, according to the study. The percentage of adults in Indiana who say they binge drink or drink heavily goes down as age increases.
Alcohol tolerance varies from person to person, so those who drink should watch how it affects them specifically, said Dr. Peter Mavrelis, a gastroenterologist who works with Indiana University Northwest.
"Just because your friend can hold down two six-packs doesn't mean you can do the same," he said.
Mavrelis also said he was surprised at how little alcohol is considered binge drinking, noting that people often consider binge drinking as drinking to the point of incapacitation. Still, he said, people should keep their alcohol consumption to less than two or three drinks a day.
Information from: The Times, _URL_
Photo courtesy Tim Pearce @ Flickr
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Time doesn't actually slow down in a crisis
By Ed Yong | May 3, 2010 9:00 am
I'm on holiday this week so I'll be reposting a few articles from the old WordPress incarnation of Not Exactly Rocket Science. Stay with it though – these are five good'uns.
The task was deceptively simple. They merely had to read two numbers that were displayed on a wrist-mounted machine called a 'perceptual chronometer'. Like a clunky digital watch, the device was programmed to show two numbers, but the catch was that the glowing digits were rapidly alternated with their negative images, where the area around the number is lit.
Perceptual chronometerAs the two images flicker more and more quickly, there comes a sudden point where they blur into a single uniform square of light. At this point, the rush of visual information overwhelms the brain of the volunteer, who is unable to resolve the two images apart.
The trio of researchers tuned the device to each volunteer's threshold of resolution – the point where they only just failed to read the numbers. They reasoned that if a scary experience really made time slow down for the volunteers, even by a tiny amount, the flickering numbers should slow down enough to pop out of the blur. The effect should be like a slow motion camera, resolving the blur of a buzzing fly into individual wing beats.
To provide the necessary fear, Stetson took his volunteers up a SCAD tower (Suspended Catch Air Device) where they were strapped to a harness and dropped from a height of 150 ft onto a safety net. As they plummeted in free-fall, they had to try and read the numbers flashing from their wrists, while an eagle-eyed experimenter watched from the top to rule out those who kept their eyes completely shut.
SCAD tower task
The volunteers failed. In fact, they read the numbers just as inaccurately as a control group who did the same task while staying on the ground. Neo, they weren't. Unlike the slowed bullet-time of The Matrix, a person's perception of events in time doesn't speed up when danger looms.
However, the volunteers did have a distorted view of time during their fall. Before they ascended the tower, Stetson asked each volunteer to reproduce how long a compatriot took to hit the net using a stopwatch. They were then asked to do the same after they'd had a go themselves. On average, the volunteers estimated that own experience took 36% longer than that of their fellows. Time didn't slow down – the volunteers just remembered that it did.
Stetson and co believe that people lay down richer, denser memories when they experience shocking events. These 'flashbulb memories' include emotional content, which involves the brain's emotional centre – the amygdala (see this earlier post about flashbulb memories in 9/11 survivors). As these memories are played back, their unusual richness could fool the brain into thinking that the recorded events took up more time than was actually the case.
Reference: Stetson, C., Fiesta, M.P., Eagleman, D.M., Burr, D. (2007). Does Time Really Slow Down during a Frightening Event?. PLoS ONE, 2(12), e1295. DOI: 10.1371/journal.pone._PHONE_
More on perception:
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Comments (17)
1. WA_side
Ha! But how do you convince people who are sure they've lived through time slowing down?
Sometimes, when I'm very focussed while playing sport, the ball can appear to move more slowly towards me, allowing me to (feel I am) react(ing) faster.
So now, I need to make my brain believe that it is an illusory memory.
Does this mean I am better at sport than I thought???
2. I had a similar thought while running a required 10 minutes cardio today in between my weight sets — "why is this the slowest 10 minutes I've ever experienced in my life?" Whereas if I'm chatting with a friend via computer or telephone time speeds up.
3. Epimetheus
How do we know that the "rush of visual information" is actually overwhelming the brain, as opposed to some bottleneck in the receiving mechanism of the eye?
4. Alex
That's an interesting point because if it is some physical maximum frame rate of sorts, above which the eye cannot distinguish images, then the experiment would be testing whether or not the physical restraints of the eye can improve in a high stress/fear situation, not whether the brain can necessarily process and respond to information faster.
5. Nelson
I also suspect that this test setup was flawed. Some aircraft simulators are sped-up to compensate for the lack of "pucker factor" that a human pilot would experience in a real cockpit.
I don't have the citations handy, but I think Euclid Holleman looked at this in the mid-70s at NASA. I've also heard this called "above real-time training" if you want some search terms.
Interesting that they estimated a 36% change, because the flight simulator folks seem to use 40% as a rule-of-thumb.
Maybe those researchers should look at flight data from actual aviation emergencies (with real fear, logged input and output data, and much more complex cognitive tasks than reading a number.)
6. Chris M.
That is quite an interesting caveat brought up by earlier commenters; if it's the higher cognitive centers in the brain that are speeding up their processing, you wouldn't necessarily see any change in the output of V1, the primary visual cortex, which is the likely limiter for persistence of vision. It's incredibly optimized already.
Anyway, interesting to see some sort of real data on this! They've successfully eliminated one possible region that could help explain the effect.
7. MW
Who can concentrate on a wrist display when falling from a great height?
I think it would be better if the display were a large one underneath the net. That is where you need to be looking for maximum scare value (and presumably maximum time-dilation.)
8. Nelson
I think the ideal task would be one where the person is responsible for making the right decision quickly to avoid harm to themselves. Of course, it may be hard to design such a test.
9. Sometimes in a crisis, there seems to be more time to make a decision and react. That's if I can see it coming. On the other hand, physical shocks like suddenly falling through a floor happen way too fast to react to, and I recall that we fall a body-length in about 1/5 second. It's an interesting question.
There may well be a training effect. After some training in sparring, many years ago, we seemed to get faster at reading situations and choosing a response. It would be interesting to design an experiment based on reaction time…. Oh, hell. Perception seems faster, too.
10. BillWhite36
#7. MW Says:
"Who can concentrate on a wrist display when falling from a great height?"
I can. I've fallen a mile over 2000 times, keeping an eye on a wrist mounted altimeter. It is amazing how much a skydiver can accomplish in 30 seconds of free-fall. It doesn't take an emergency for time to slow down – remember, "A watched pot never boils." On the other hand, try running to the bathroom for a bowel movement during a TV commercial. The next program segment is half over before you can get back!
I'm bothered by the headline on this article: Time doesn't actually slow down in a crisis. Almost a silly statement. If time actually slowed down for the person in crisis, we'd all be out of sync with one another. Maybe it averages out, since we all face a crisis now and then. :o)
And I think the experiment was flawed because the test subjects weren't really all that "scared" – they knew the experimenters weren't going to let them fall to their deaths. Crisis diminished.
The question should be, "Does time seem to slow down in a crisis?" IMHO, it's a definite "yes". Our perception of time certainly changes depending on our circumstances at the moment.
11. Nelson
Still there's the problem of testing whether we actually think faster in a crisis, or if it only seems so in retrospect.
12. Daniel J. Andrews
I'm wondering how they managed to convince enough subjects to participate in an experiment where they were thrown off a 150′ tower.
13. Art Chaney
In my opinion time does slow down when we think faster. I was in a car accident and I specifically remember the air bag opening up in slow motion like a time lapse film of a flower blooming on the discovery channel. It had a cross hair right in the middle of it. I also remember (previous to the airbag opening) thinking about what parts of my body were the most important to protect. I decided I needed to cover my head with my hands then I decided that it would be better to see things coming at me so I could duck out of the way…so i moved my hands away from my head. I remembered seeing the grass coming by the window then the airbag opened. Then I saw it retracting back slowly and I wondered why it was retracting back. Anyway I made a theory from it. Arts theory of
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cordage (kôrˈdĭj) [key], collective name for rope and other flexible lines. It is used for such purposes as wrapping, hauling, lifting, and power transmission. Early man used strips of hide, animal hair, and plant materials. Hemp and flax were formerly standard in Europe and America but were largely replaced in the 19th cent. by hard fibers, especially Manila hemp and sisal. In the 20th cent. the natural fibers were replaced in many applications by synthetic fibers such as nylon and polyester. The fibers are straightened, usually by combing, then spun into yarn. Twine, which is sometimes called cord, is formed by wrapping two or more yarns together. By twisting together a number of yarns, a strand is formed. By twisting together three or more strands, a rope is produced. A cable-laid rope is formed from three or more ropes. In general a synthetic fiber rope lasts much longer and is much stronger than a natural fiber rope. Steel wire, often with a fiber core, is also used for rope.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
More on cordage from Fact Monster:
See more Encyclopedia articles on: Technology: Terms and Concepts
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Nova Scotia is one of Canada's three Maritime provinces and is the most populous province of the four in Atlantic Canada. Located almost exactly halfway between the Equator and the North Pole, its provincial capital is Halifax. Nova Scotia is the second-smallest province in Canada with an area of 55,284 square kilometres (21,300 sq mi), including Cape Breton and some 3,800 coastal islands. As of 2011, the population was 921,727, making Nova Scotia the second-most-densely populated province in Canada.
Nova Scotia was already home to the Mi'kmaq people when French colonists established Port Royal, Nova Scotia, the first permanent European settlement in North America north of Florida in 1605. Almost one hundred and fifty years later, the first English and German settlers arrived with the founding of Halifax (1749). The first Scottish migration was on the Hector (1773) and then the first Black migration happened after the American Revolution (1783). Despite the diversity of the cultural heritage of Nova Scotia, much of the twentieth-century tourism efforts focused primarily on all things Scottish. Many recent tourism efforts embrace and showcase Nova Scotia's diversity.
In 1867 Nova Scotia was one of the three founding provinces of the Canadian Confederation.
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Preventing Particle Penetration
With residents' health increasingly dependent on a home's indoor air quality, ventilation strategies become more important than ever.
As anyone who has stood over a smoky campfire can attest, breathing in fine particles is a health hazard.The health risk associated with inhaling dust and other small particles is directly related to the level of exposure, which is why agencies such as the Ontario Ministry of the Environment have set up outdoor atmospheric sampling stations to measure the levels of fine particles in outdoor air. But given that people spend most of their time indoors, indoor particle exposure may be more important than outdoor exposure (see "Sources of Indoor Particles," p. 14).
Unfortunately, there is little or no information now about how different ways of building, heating, cooling, and ventilating a home affect how well it guards the occupants from fine particles coming in from the air outside.With asthma, allergies, and other respiratory ailments that are linked with indoor air quality (IAQ) on the rise, better IAQ means better health for consumers.And knowing what ventilation strategies provide the best IAQ can help consultants, contractors, and builders to design and build healthier homes. Canada Mortgage and Housing Corporation (CMHC) is the federal agency responsible for housing research.CMHC hired Dara Bowser of Bowser Technical, Incorporated, to provide some of that information by investigating how ventilation and filtration affect the indoor/outdoor ratio of particles in a house, and by determining the filtering effect of the house envelope on incoming air.
Outdoor Particle Penetration
Outdoor particles can penetrate either through the building envelope or through an intentionally created air inlet.The paths range from the relatively large and direct, such as—in Canada at least—the combustion air inlet for gas furnaces and water heaters, which are usually 4–6-inch open pipes, to the lengthy and convoluted, such as paths through the wall assembly.The pressure causing the air movement may be due to naturally occurring forces, such as wind and indoor/outdoor temperature differences; or the pressure may be caused by the operation of mechanical equipment within the home, such as the outdoor air supply connection to an air handler, an exhaust-only ventilation system, or a clothes dryer.
In Canada, some ventilation systems consist of an intake duct connected to the return air side of the furnace.These are sometimes called nonpowered systems, but in reality the operation and suction pressure created by the furnace fan governs the rate of intake air flow. Other ventilation systems are based on a central heat recovery ventilator (HRV).HRVs are equipped with filters that are capable of removing large particles that would block the heat exchange passages, but these filters are not usually effective for removing fine particles from the airstream.
When a central forced-air system is also installed in a home, the HRV often has its outdoor air supply connected to the return air duct of the central forcedair system. Internal fans and controls manage the HRV flow rate. In both of these systems, the incoming outdoor air is passed through the central forced-air system's main filter before being delivered into the occupied spaces of the home.The various filters in central forced-air systems remove anywhere from none of the fine particles to more than 90% of them.
Testing Ventilation Strategies
Our experiments took place in a home in Brantford, Ontario, Canada.Two adults lived in the house at the time of our tests.The test conditions represent typical southern Ontario spring and summer conditions. During our tests, the air handling and ventilation systems were operated continuously, with all the doors and windows closed.The continuous operation of ventilation systems is becoming more popular in Canada as the housing stock becomes more airtight, residents become more aware of IAQ, and summer air conditioning becomes more prevalent.Also, public health officials recommend that people who have respiratory problems caused by outdoor air particles keep their doors and windows closed. The Brantford house is considered to be moderately airtight by Canadian standards, with an effective leakage area (ELA) of 114 square inches (733 cm2) and an ACH50 of 5.33.
The Brantford house consists of a basement and an upper floor.The upper floor contains the bedrooms, living room, and kitchen. The basement contains the mechanical room and a home office.We located the instruments for the experiment in the mechanical room. One person was in the home during the day (mostly in the basement).Two people were in the home during the evening and at night (mostly on the upper floor).
We measured airborne fine particles
- outside (under the overhanging roof of a covered patio);
- in the air intake from outside;
- in the home office;
- in the central air handling system (the sample consisted of mixed return and outside air); and
- in one bedroom.
We tested for fine-particle penetration for five distinct ventilation modes.These were
- Supply Only, No Filtration;
- Exhaust Only, No Filtration;
- Balanced, No Filtration;
- Balanced, with HEPA Intake Filter; and
- Supply Only, with HEPA Intake Filter.
Ventilation rates ranged between 1.20 and 0.71 ACH and were selected to ensure that in the Supply Only modes, all of the incoming air passed though the ventilation system, and in the Exhaust Only mode, all of the incoming air passed through the building envelope. Continuous real-time measurements of indoor and outdoor particle levels were made during the day and night.We also measured air temperature, air pressure, wind speed, and ventilation flows continuously.A total of 428 data hours were used for data analysis.
We calculated a house average value using the average of the office and bedroom values. Indoor particle levels were reported as the amount of particles less than 1 micron (PM1) and as the amount of particles less than 10 microns (PM10). Indoor/outdoor ratios were also reported.An indoor/outdoor ratio of 0.5 indicates, for example, that the indoor levels were 50% of the outdoor levels.A ratio of 1.5 indicates that the indoor levels were 150% of the outdoor levels.
Comparing Ventilation Strategies
In general, the systems with HEPA filtration of the outdoor air provided the best control of indoor particles coming from outdoors. The systems that supplied outdoor air directly to the living space without filtration didn't do well in keeping particles out.The Exhaust Only system, which relies on the building envelope to filter out incoming particles, performed in the middle, halfway between the systems with HEPA filtration and the other two systems without filtration (see Figures 1 and 2).
The dynamic functioning of the systems can be seen in sample data sets. With the Supply Only HEPA and the Balanced HEPA systems respectively, the indoor particle levels compared to the outdoor levels show only a mild trend. The indoor particle levels appear to be related principally to occupant activity, rather than to outdoor levels.
With the Exhaust Only system, there is a distinct relationship between indoor particle levels and outdoor particle levels, but there is a significant time lag between the indoor and outdoor levels, and the effects of occupant activity remain apparent (see Figure 3). With the Supply Only, No Filtration system, indoor particle levels are essentially a mirror of outdoor particle levels, with a lag time that is attributable to the settlement rate of the indoor particles (see Figure 4).The effect of outdoor particle penetration is much greater than the effect of occupant activity.
Recommended Ventilation Strategies
From our measurements of particle penetration into a house under various ventilation conditions,we can offer some practical advice.
Direct entry of unfiltered air. The direct entry of air that is not filtered for particles will raise the indoor levels of respirable particles. These levels will be higher than those normally expected in a home that does not have direct entry of outdoor air, or in which the entry routes for outdoor air are filtered.This is true even in comparison to Exhaust
Only ventilation systems with similar air change rates, as the building envelope of the house is capable of removing a substantial portion of the incoming fine particles, even those with relatively small diameters.
For houses that are currently equipped with an HRV-based system that is not connected to a central forcedair recirculation system, a fine-particle filtering system should be considered for the incoming air. For homes equipped with an outdoor air intake directly connected to the return of a forced-air system, or where an HRV is connected to the forced-air system, the use of a fine-particle air filter for the central system should be considered. Such a fineparticle filter will treat incoming outdoor air as well as recirculated house air.
Exhaust Only ventilation. Exhaust Only ventilation systems are moderately effective at keeping fine particles out of the living spaces of a home, due to the filtering effect of the building envelope. While this filtering effect may vary depending on how the house was constructed, it is reasonable to conclude that Exhaust Only systems are superior to those that allow unfiltered air to enter directly into the house. In the absence of combustion equipment that could be depressurized by the action of an Exhaust Only ventilation system, this system could be operated year-round in Canada.The Exhaust Only system can be beneficial during winter operation, because the entry of dry outside air can
prevent the wetting of the building envelope by exfiltrating air.
In southern climates, where building interiors are cooler than the outdoor dew point, use of an Exhaust Only system may result in the wetting and subsequent deterioration of the building envelope.
Supply Only ventilation with filtration. Although the Supply Only system with filtration performed better in keeping outdoor particles out of the house,we can't recommended it for wintertime use in heating climates. In the winter, exfiltrating air forced into the building envelope by the operation of such a system could cause wetting of the building envelope, leading once again to deterioration.A Supply Only ventilation system
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Mysterious spinning super-magnetic stars:
What the Heck is a Magnetar?
NASA artist depiction of a magnetar in deep space
NASA artist depiction of a magnetar
A magnetar is a weird duck, indeed. It's a spinning neutron star with a super-strong magnetic field a thousand trillion times stronger than Earth's magnetic field. To visualize it, you have to know about neutron stars, pulsars and SGRs. Astronomers have wondered for a long time why certain supernova explosions create magnificent nebulas, yet leave no spinning pulsar at the center. This abnormal situation has been a problem for astronomers trying to calculate star births and deaths and the ages of galaxies and the universe.
An Extraordinary Flare
On December 27, 2004, astronomers detected a flash of energy from across our Milky Way galaxy so powerful that it bounced off the Moon and lit up Earth's upper atmosphere.
The flash, which lasted more than one-tenth of a second, was brighter than anything ever detected from beyond our Solar System.
NASA and European astronomy satellites and many radiotelescopes on Earth recorded the flash.
Scientists discovered the flash of energy came from a magentar the neutron star SGR 1806-20 some 50,000 lightyears away in an area of Earth's sky known as the constellation Sagittarius.
Its apparent magnitude was brighter than a full Moon and all previously recorded star explosions. Most of the energy was in invisible gamma-rays, which are far more energetic than visible light or X-rays.
SGR 1806-20 is known to be a soft gamma repeater (SGR) because it randomly flares up and releases gamma rays. Only four SGRs are known.
The December 2004 giant flare on SGR 1806-20 was millions to billions of times more powerful than typical SGR flares.
For one-tenth of a second, the giant flare unleashed more energy than the Sun emits in 150,000 years.
Magnetic fields surrounding the magnetar probably was responsible for the outbursts.
Understanding began to dawn on scientists in 1979 when gamma ray detectors on nine spacecraft spread out across our Solar System recorded an intense burst of radiation. While the energy spike lasted just 2/10th of a second, it carried as much energy as our Sun releases in 1,000 years. That compared with most such bursts, which release only as much energy as the Sun releases in one year.
The big radiation spike was followed by a 200-second wave of energy pulsing every eight seconds. The radiation burst was coming from a supernova remnant known as N49 in the galaxy known as the Large Magellanic Cloud.
Scientists spotted something odd right away. N49 was only a few thousand years old, yet its eight-second spin rate would have been typical of a much older neutron star. Something was putting the brakes on and slowing down the spinning pulsar.
In 1986, astrophysicists realized they had two more objects like N49. Each sent out low-energy gamma rays in repeated bursts, while gamma ray bursts from other sources usually are one-time events.
They dubbed this new kind of deep-space object soft gamma repeater, or SGR for short. The N49 object was designated SGR 0526-66 for its position in the sky. The others were labeled SGR 1806-20 and 1900+14. Both are in our own Milky Way galaxy. SGR 1806-20 is one of the most active, most energetic of the Soft Gamma Repeaters.
From 1986, the mysterious Soft Gamma Repeaters were recognized as a separate, very peculiar class of star because of their telltale outbursts. But, exactly how were they different?
There were numerous theories until November 1996 when an instrument known as the Burst and Transient Source Experiment aboard the Compton Gamma Ray Observatory (GRO) spacecraft detected a new energy outburst from SGR 1806-20.
Then the Rossi X-ray Timing Explorer (RXTE) spacecraft captured several hours worth of data as bursts came in bunches that had not been seen before. Combining data from both satellites gave astronomers the ability to make a more sensitive search andto verify analyses of the data.
RXTE carries instruments that read data quickly. While most telescopes really take time exposures, RXTE's instrument known as the Proportional Counter Array acts like a fast electronic counter which searches for a pattern in the X-rays it receives from deep space.
The new information was compared with older data which had been gathered by Japan's Advanced Satellite for Cosmology and Astrophysics (ASCA) spacecraft in 1993. It had observed SGR 1806-20 while it was not sending out burst. ASCA data was important as astronomers established that the SGR was associated with a supernova remnant.
NASA artist concept of magnetar SGR locations along the Milky Way
NASA artist concept of where magnetar
SGRs may be located along the Milky Way
Finding the pulses in the RXTE data allowed astronomers to go back and also find it in the ASCA data, which removed anydoubt that the pulses could be from some previously unknown object in RXTE's field of view.
In the time between the ASCA and RXTE observations, SGR 1806-20 had slowed by 8/1,000th of a second. That difference might seem miniscule, but it happened in less than four years to an object with more mass than our Sun.
Not ordinary pulsars. Having established that SGR 1806-20 is associated with a rapidly slowing pulsar, the astronomers need to figure out what might fit that profile. Of course, proving what something is sometimes involves proving what it is not. The scientists thought that SGRs were objects they referred to as magnetars, but first they had to eliminate objects other than ordinary pulsars as the sources. Then they had to rule out possibilities other than magnetars as the answer.
The first possibility they had to examine was accretion where material from another star is scooped up by the pulsar, or the magnetar. Radio telescope observations at the National Radio Astronomy Observatory ruled out accretion when they showed that SGR 1806-20 coincides with a supernova remnant known as SNR G10.0-0.3. Radio broadcasts from that supernova remnant suggest a compact shape which may be orbiting a nearby massive blue star every 10 years. Since 1806's own stellar wind is too powerful to let material fall inward, it can't be an accreting pulsar.
Astronomers found that the pulsar was slowing down at a rate that suggested a magnetic field strength of about 800 trillion Gauss, which is a strength similar to that predicted in theory for magnetars. By comparison, Earth's magnetic field is a mere 0.6 Gauss at the poles. The maximum created in laboratories is 1 million Gauss. Normal radio pulsars reach about 1 trillion to 5 trillion Gauss, strong but still short of a magnetar.
Extraordinarily hot. The strong magnetic field keeps the star very hot, at about 10 million degrees C (18 million deg. F) at the surface. That powers the X-rays coming from its rotating surface.
Neutron stars are the only stars with a solid surface crust about six-tenths of a mile deep covering a thick fluid of neutrons over either a superfluid or solid core of subatomic particles. On the star's surface, a chunk of magnetizable metal like iron would feel a force equal to 150 million times the Earth's gravitational pull on it. Movement of that strong magnetic field would wrinkle the crust of the neutron star and cause starquakes that would be the source of the soft gamma-ray bursts.
Today, only about 12 magnetars have been found among the millions of regular neutron stars in our Milky Way galaxy and neighboring galaxies.
The crust is believed to be stable in ordinary neutron stars, but in magnetars, the crust probably is stressed by unbearable forces as the colossal magnetic field drifts through it. That deforms the crust and cracks it. Violent seismic waves then shake the star's surface, generating so-called Alfven waves -- reminescent of a Slinky toy -- which energize clouds of particles above the surface of the star. It also drags the star down, slowing it to about a ten-second period in just 10,000 years, which is about the age and speed of SGR 1806-20.
Even stranger. Astronomers think that, eventually, magnetars may become even more strange objects.
Six objects referred to as anomalous X-Ray pulsars (AXPs) are known to be different from most X-ray pulsars. The X-ray colors of those anomalous pulsars are very red compared to something like blue for normal pulsars. Their rotational periods also slow faster than other stars.
Astronomers suggest there could be as many as one to 100 million magnetars have in our Milky Way galaxy. Also, many supernova remnants that lack pulsars actually may have them in the form of invisible, dead pulsars that exploded as supernovas, sputtered as SGRs concealing magnetars, then faded through the AXP stage to become invisible.
Learn more about magnetars:
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(PhysOrg.com) -- Because we're so smart compared to other species that live on this planet, people tend to ascribe certain abilities as innately human. One of these traits is the ability to lie or cheat. This is because doing so seems to imply a high order of intelligence. Unfortunately, as with many other traits that have once been thought uniquely human, lying, or bluffing appears to occur in other species as well, or at least in one, the lowly male crayfish. In a recent study, Michael Angilletta from Arizona State University and Robbie Wilson of the University of Queensland, found that male crayfish use claw size to bluff their way out of fights with other males. They have published their observations in the Royal Society journal, Biology Letters.
Crayfish, as most who have ever seen them can attest, are naturally aggressive. If you stick your hand in the water, rather than run or hide, a crayfish will grab your fingers with its sharp claws and try to defeat you. Thus, it should come as no surprise that they are just as nasty regarding one another. Upon two males meeting, their natural inclination is to start fighting. But then, sometimes, they don't. Evolution has added a layer of protection to keep them from completely wiping out their own species by endowing males with different sized claws. Oddly, instead of jumping into action, as might be expected, two males will first size one another up. They'll lift their claws to show the other how big they are, then lay them down so the other can poke and prod them a little. If one is satisfied that the other has bigger claws, he will leave the scene and a fight will be avoided, which is a good thing, because when they do fight, limbs can be severed and sometimes one or the other ends up dead.
But there is more to the story as Angilletta and Wilson found out, because all is not as it seems. They found after studying 97 of the males in action on North Stradbroke Island in Queensland, that claw size doesn't equate to strength. Some males with large claws had weak muscles, while some with smaller claws had strong muscles; and in crawfish, muscle is more important because it can mean the difference between causing an annoying pinch versus severing a limb or other important body part.
The research duo surmise that the crayfish are fully aware of the actual strength of their pinch and thus resort to bluffing if their muscles aren't up to snuff when they run into another male with smaller, but potentially stronger claws. And because the smaller clawed rival falls for it as much as 80% of the time, many unnecessary fights and the carnage they cause can be avoided.
Thus, clearly humans, are not the only species able to bluff their way out of fight.
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More information: Cryptic asymmetry: unreliable signals mask asymmetric performance of crayfish weapons, Biology Letters, Published online before print March 14, 2012, doi: 10.1098/rsbl.2012.0029
Animals commonly use their limbs as signals and weapons during territorial aggression. Asymmetries of limb performance that do not relate to asymmetries of limb size (cryptic asymmetry) could substantially affect disputes, but this phenomenon has not been considered beyond primates. We investigated cryptic asymmetry in male crayfish (Cherax dispar), which commonly use unreliable signals of strength during aggression. Although the strength of a chela can vary by an order of magnitude for a given size, we found repeatable asymmetries of strength that were only weakly related to asymmetries of size. Size-adjusted strength of chelae and the asymmetry of strength between chelae were highly repeatable between environmental conditions, suggesting that asymmetries of strength stemmed from variation in capacity rather than motivation. Cryptic asymmetry adds another dimension of uncertainty during conflict between animals, which could influence the evolution of unreliable signals and morphological asymmetry.
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