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Messages - Mostakima Mafruha Lubna

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I must try some of these tips, thank you for sharing.

Very handy information, thank you for sharing.

Thank you for sharing this informative post.

Textile Engineering / Re: Intelligent textiles -(part2)
« on: April 21, 2015, 04:15:36 PM »
Nice to know these information, thank you.

Through a combination of data analysis and numerical modeling work, researchers have found a record of the ancient Moon-forming giant impact observable in stony meteorites. Their work will appear in the April 2015 issue of the Journal Science. The work was done by NASA Solar System Exploration Research Virtual Institute (SSERVI) researchers led by Principal Investigator Bill Bottke of the Institute for the Science of Exploration Targets (ISET) team at the Southwest Research Institute and included Tim Swindle, director of the University of Arizona's Lunar and Planetary Laboratory.

The inner Solar System's biggest known collision was the Moon-forming giant impact between a large protoplanet and the proto-Earth. The timing of this giant impact, however, is uncertain, with the ages of the most ancient lunar samples returned by the Apollo astronauts still being debated. Numerical simulations of the giant impact indicate this event not only created a disk of debris near Earth that formed the Moon, but it also ejected huge amounts of debris completely out of the Earth-Moon system. The fate of this material, comprising as much as several percent of an Earth mass, has not been closely examined until recently. However, it is likely some of it blasted main belt asteroids, with a record plausibly left behind in their near-surface rocks. Collisions on these asteroids in more recent times delivered these shocked remnants to Earth, which scientists have now used to date the age of the Moon.

The research indicates numerous kilometer-sized fragments from the giant impact struck main belt asteroids at much higher velocities than typical main belt collisions, heating the surface and leaving behind a permanent record of the impact event. Evidence that the giant impact produced a large number of kilometer-sized fragments can be inferred from laboratory and numerical impact experiments, the ancient lunar impact record itself, and the numbers and sizes of fragments produced by major main belt asteroid collisions.

Once the team concluded that pieces of the Moon-forming impact hit main belt asteroids and left a record of shock heating events in some meteorites, they set out to deduce both the timing and the relative magnitude of the bombardment. By modeling the evolution of giant impact debris over time and fitting the results to ancient impact heat signatures in stony meteorites, the team was able to infer the Moon formed about 4.47 billion years ago, in agreement with many previous estimates. The most ancient Solar System materials found in meteorites are about one hundred million years older than this age.

Insights into the last stages of planet formation in the inner solar system can be gleaned from these impact signatures. For example, the team is exploring how they can be used to place new constraints on how many asteroid-like bodies still existed in the inner Solar System in the aftermath of planet formation. They can also help researchers deduce the earliest bombardment history of ancient bodies like Vesta, one of the targets of NASA's Dawn mission and a main belt asteroid whose fragments were delivered to Earth in the form of meteorites. It is even possible that tiny remnants of the Moon-forming impactor or proto-Earth might still be found within meteorites that show signs of shock heating by giant impact debris. This would allow scientists to explore for the first time the unknown primordial nature of our homeworld.

Co-author Swindle, who specializes in finding the times when meteorites or lunar samples were involved in large collisions, said: "Bill Bottke had the idea of looking at the asteroid belt to see what effect a Moon-forming giant impact would have, and realized that you would expect a lot of collisions in the period shortly after that.

"Here at LPL, we had been determining ages of impact events that affected meteorites, and when we got together, we found that our data matched his predictions," he added. "It's a great example of taking advantage of groups that work in two different specialties - orbital dynamics and chronology - and combining their expertise."

Intriguingly, some debris may have also returned to hit the Earth and Moon after remaining in solar orbit over timescales ranging from tens of thousands of years to 400 million years.

"The importance of giant impact ejecta returning to strike the Moon could also play an intriguing role in the earliest phase of lunar bombardment," said Bottke, who is an alumnus of the University of Arizona's Lunar and Planetary Laboratory. "This research is helping to refine our time scales for 'what happened when' on other worlds in the Solar System."

Yvonne Pendleton, Director of the NASA SSERVI Institute, notes: "This is an excellent example of the power of multidisciplinary science. By linking studies of the Moon, of main belt asteroids, and of meteorites that fall to Earth, we gain a better understanding of the earliest history of our Solar System."

### This research was supported in part by NASA's Solar System Exploration Research Virtual Institute (SSERVI) at NASA's Ames Research Center in Moffett Field, California. SSERVI is funded by the Science Mission Directorate and Human Exploration and Operations Mission Directorate at NASA Headquarters to enable cross-team and interdisciplinary research that pushes forward the boundaries of science and exploration.

Environmental Science and Disaster Management / Do Black Holes Die?
« on: April 21, 2015, 04:05:46 PM »
Black holes are enormous cosmic bodies with immense gravitational pull. Over time black holes keep sucking in matter around it and keep getting bigger and bigger.  Do black holes die or continue for ever ? As black hole feed on matter, principles of quantum mechanics eventually lead to demise of black holes.

In quantum mechanics, subatomic positive and negative particles are continuously created and annihilated into energy. At times when these particles are created at event horizon gravity of black hole pull in negative particles while positive particles end up escaping into the space. This phenomena was first described by Stephen Hawking thus also known Hawking’s radiation. Over time, the black hole emits energy in from of positive particles leading to lose of mass. Black holes will continue to loss its mass and eventually evaporate to nothing and/or they may become unstable cosmic bodies eventually ending with explosive gamma rays bursts.

New studies by astronomers are slowly throwing some light on dark matter, the invisible and mysterious stuff that scientists believe makes up much of the universe. For the first time, astronomers believe they've observed the interactions of dark matter via a factor other than the force of gravity.

Dark matter's gravitational interactions with the parts of the universe that we can actually see are the only reason that we know it exists at all. Weirdly, it has seemed until now that dark matter has no other known interactions with anything in the universe, including itself. A recent study seemed to back up the notion that bits of dark matter appear to just drift through space, and not even interact with each other.

However, new observations of the simultaneous collision of four galaxies in the galaxy cluster Abell 3827 – using the European Southern Observatory's Very Large Telescope (VLT) in Chile and a technique called "gravitational lensing" – seemed to show a "clump" of dark matter around one of the galaxies, lagging a bit behind that galaxy.

This sort of lollygagging is something that scientists have predicted might be observable during collisions if dark matter were to interact with itself through some force other than gravity, even slightly.

"We used to think that dark matter just sits around, minding its own business, except for its gravitational pull," said Richard Massey at Durham University, lead author of a paper on the study. "But if dark matter were being slowed down during this collision, it could be the first evidence for rich physics in the dark sector – the hidden Universe all around us."

Massey was also part of the study from last month which seemed to show that dark matter does interact even with itself at all. The researchers say the new findings do not necessarily conflict with the earlier study, however. That's because the new research looks at the motion of individual galaxies rather than galaxy clusters, along with the fact that collisions between them may have lasted longer, allowing a small frictional force to build up over a time span lasting between "only" 100 million years to about a billion years.

Massey believes that when looked at together, the two studies may actually work to put limits on the behavior of dark matter. "We are finally homing in dark matter from above and below – squeezing our knowledge from two directions," he said. "Dark matter, we’re coming for you."

The research paper was recently published in the journal Monthly Notices of the Royal Astronomical Society. Source: ESO

One of the biggest questions to date pertains to the expansion of the universe since the “Big Bang”. While some believe the universe is expanding rapidly, still others think the universe is moving outward at a much slower pace. Which idea is correct?

Fast or slow The basic idea that the universe is expanding at a rapid pace comes from observation of supernovae. Different types of supernovae have been found, for instance, type Ia supernovae, which are uniform and used as beacons to probe the outer reaches of space. Peter Milne of the Department of Astronomy and Steward Observatory reported that supernovae are found in many different populations with varying degrees of brightness. This poses many questions following. “Differences in brightness are not random. There are two categories of supernovae: the nearby minority and the distant majority stars,” said Milne. According to the idea of consistent growth, previous assumptions say that supernovae are the same whether near or far, moving at the same rate of expansion. This could be false. Contrary to previous belief, signs point to a recent rapid expansion.
The popular idea of a rapidly expanding universe The view of the fast bursting universe resulted in the 2011 Nobel Prize in Physics granted to Brian P. Schmidt and three other scientists. They all believed that dim stars signified supernovae which moved farther away from the other stars, much farther than they should, and at a faster pace. This is what stemmed the belief that the speed that galaxies move away from each other is increasing. “Many scientists use the type la supernovae as a guidepost. Type Ia supernovae are all similar-shine equally bright after they explode- than other stars in the galaxy. Since they should be the same as other stars, but are not, scientists assume they are farther away, pushed by rapid expansion,” says Milne.
Observations Observations from The Hubble Space Telescope and NASA’s Swift Satellite were used to study type Ia supernovae in ultraviolet and visible light. Milne, together with Ryan J. Foley of the University of Illinois-Urbana Campaign, Gautham Narayan of the National Optical Astronomy Observatory of Tucson and Peter J. Brown of Texas A&M collected crucial data with these instruments. Differences between the shifts from blue to red or vice versa (indicating different populations of supernovae) were followed by observations in the ultraviolet light. “Results are great!” Says Neil Gehrels investigator of the Swift Satellite. “This shows how our satellite can respond to new phenomenon in a quick manner.”

Very interesting information  ???

xtreme success results from an extreme personality and comes at the cost of many other things. Extreme success is different from what I suppose you could just consider 'success', so know that you don't have to be Richard or Elon to be affluent and accomplished and maintain a great lifestyle. Your odds of happiness are better that way. But if you're extreme, you must be what you are, which means that happiness is more or less beside the point. These people tend to be freaks and misfits who were forced to experience the world in an unusually challenging way. They developed strategies to survive, and as they grow older they find ways to apply these strategies to other things, and create for themselves a distinct and powerful advantage. They don't think the way other people think. They see things from angles that unlock new ideas and insights. Other people consider them to be somewhat insane.
e obsessed.

Be obsessed.

Be obsessed.

If you're not obsessed, then stop what you're doing and find whatever does obsess you. It helps to have an ego, but you must be in service to something bigger if you are to inspire the people you need to help you  (and make no mistake, you will need them). That 'something bigger' prevents you from going off into the ether when people flock round you and tell you how fabulous you are when you aren't and how great your stuff is when it isn't. Don't pursue something because you "want to be great". Pursue something because it fascinates you, because the pursuit itself engages and compels you. Extreme people combine brilliance and talent with an *insane* work ethic, so if the work itself doesn't drive you, you will burn out or fall by the wayside or your extreme competitors will crush you and make you cry.
Follow your obsessions until a problem starts to emerge, a big meaty challenging problem that impacts as many people as possible, that you feel hellbent to solve or die trying. It might take years to find that problem, because you have to explore different bodies of knowledge, collect the dots and then connect and complete them.

It helps to have superhuman energy and stamina. If you are not blessed with godlike genetics, then make it a point to get into the best shape possible. There will be jet lag, mental fatigue, bouts of hard partying, loneliness, pointless meetings, major setbacks, family drama, issues with the Significant Other you rarely see, dark nights of the soul, people who bore and annoy you, little sleep, less sleep than that. Keep your body sharp to keep your mind sharp. It pays off.

Learn to handle a level of stress that would break most people.
Don't follow a pre-existing path, and don't look to imitate your role models. There is no "next step". Extreme success is not like other kinds of success; what has worked for someone else, probably won't work for you. They are individuals with bold points of view who exploit their very particular set of unique and particular strengths. They are unconventional, and one reason they become the entrepreneurs they become is because they can't or don't or won't fit into the structures and routines of corporate life. They are dyslexic, they are autistic, they have ADD, they are square pegs in round holes, they piss people off, get into arguments, rock the boat, laugh in the face of paperwork. But they transform weaknesses in ways that create added advantage -- the strategies I mentioned earlier -- and seek partnerships with people who excel in the areas where they have no talent whatsoever.

They do not fear failure -- or they do, but they move ahead anyway. They will experience heroic, spectacular, humiliating, very public failure but find a way to reframe until it isn't failure at all. When they fail in ways that other people won't, they learn things that other people don't and never will. They have incredible grit and resilience.
They are unlikely to be reading stuff like this. (This is *not* to slam or criticize people who do; I love to read this stuff myself.) They are more likely to go straight to a book: perhaps a biography of Alexander the Great or Catherine the Great* or someone else they consider Great. Surfing the 'Net is a deadly timesuck, and given what they know their time is worth -- even back in the day when technically it was not worth that -- they can't afford it.

I could go on, it's a fascinating subject, but you get the idea. I wish you luck and strength and perhaps a stiff drink should you need it.

Thank you for this handy post, I must try some of these suggestions.

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