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How scientists and supercomputers could make oceans drinkable- physics know

Aleksandr Noy

Senior Research Scientist,

Lawrence Livermore National Laboratory

Removing salt from seawater is an enormous challenge. Researchers may have the answer – but it will require a whole lot of processing power.

ALEKSANDR NOY HAS big plans for a very small tool. A senior research scientist at Lawrence Livermore National Laboratory, Noy has devoted a significant part of his career to perfecting the liquid alchemy known as desalination – removing salt from seawater. His stock-in-trade is the carbon nanotube. In 2006, Noy had the audacity to embrace a radical theory: maybe nanotubes – cylinders so tiny, that they can be seen only with an electron microscope – could act as desalination filters. It depended on just how wide the tubes were. The opening needed to be big enough to let water molecules flow through but small enough to block the larger salt particles that make seawater undrinkable. Put enough carbon nanotubes together and you potentially have the world’s most efficient machine for making clean water

Exascale computing can help solve fresh water shortagesFaster supercomputers will aid researchers who are studying desalination and depollution filters to boost the amount of drinkable water in the world

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The Nobel Prize in Physics 2017-physicsknow

Nobel Prize in Physics 2017

Gravitational wave researchers win Nobel Prize

Rainer Weiss (left) from MIT, Barry Barish from Caltech, and Kip Thorn from Caltech all shared the 2017 Nobel Prize in Physics.

Three American physicists have won the 2017 Nobel Prize in Physics for their contribution to detecting gravitational waves. 

The Nobel Prize in Physics 2017 was divided, one half awarded to Rainer Weiss, the other half jointly to Barry C. Barish and Kip S. Thorne "for decisive contributions to the LIGO detector and the observation of gravitational waves".

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physics is in our everyday life |PhysicsKnow|

physics is in our everyday life |PhysicsKnow|

Like our facebook page https://www.facebook.com/physicsknow Follow on twitter https://twitter.com/physicsknow visit our blog https://physicsknow.blogspot.in/

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This Month in Physics History- September 1905 -PhysicsKnow

September 1905: Einstein's Most Famous Formula

 Einstein's Most Famous Formula-

   physicsknow

Although several renowned scientists published papers bearing on the theory of special relativity prior to 1900 - including Maxwell, Lorentz and Henri Poincaré - 1905 is generally recognized as the birth year of special relativity. That year saw publication of two important papers on the subject, by an obscure patent clerk named Albert Einstein.

Having failed to obtain a university post teaching mathematics and physics, Einstein was working in the patent office in Bern, Switzerland, when he completed an astonishing range of theoretical physics publications, all written in his spare time with

out the benefit of close contact with scientific literature or colleagues.

In June, 1905, Einstein proposed what we know today as the special theory of relativity. He based his theory on a reinterpretation of the classical principle of relativity, which postulates that the laws of physics must have the same form in any frame of reference. The theory also assumed that the speed of light remained constant in all frames of reference, as required by Maxwell's theory.

But it was later that year, in a paper received by the Annalen der Physik on September 27, applying his equations to study the motion of a body, that Einstein showed that mass and energy were equivalent, a startling new insight he expressed in a simple formula that became synonymous with his name: E=mc2. However, full confirmation of his theory was slow in coming. It was not until 1933, in Paris, when Irène and Frédéric Joliot-Curie took a photograph showing the conversion of energy into mass, in which a quantum of light carries energy up from beneath and converts into mass in the middle, creating two particles which curve away from each other.

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NASA say-Large Asteroid to Safely Pass Earth on Sept. 1 2017 - physicsknow

Large Asteroid to Safely Pass Earth on Sept. 1

Asteroid Florence, a large near-Earth asteroid, will pass safely by Earth on Sept. 1, 2017, at a distance of about 4.4 million miles, (7.0 million kilometers, or about 18 Earth-Moon distances). Florence is among the largest near-Earth asteroids that are several miles in size; measurements from NASA's Spitzer Space Telescope and NEOWISE mission indicate it’s about 2.7 miles (4.4 kilometers) in size.  

“While many known asteroids have passed by closer to Earth than Florence will on September 1, all of those were estimated to be smaller,” said Paul Chodas, manager of NASA’s Center for Near-Earth Object Studies (CNEOS) at the agency's Jet Propulsion Laboratory in Pasadena, California. “Florence is the largest asteroid to pass by our planet this close since the NASA program to detect and track near-Earth asteroids began.”

This relatively close encounter provides an opportunity for scientists to study this asteroid up close. Florence is expected to be an excellent target for ground-based radar observations. Radar imaging is planned at NASA's Goldstone Solar System Radar in California and at the National Science Foundation's Arecibo Observatory in Puerto Rico. The resulting radar images will show the real size of Florence and also could reveal surface details as small as about 30 feet (10 meters).

Asteroid Florence was discovered by Schelte "Bobby" Bus at Siding Spring Observatory in Australia in March 1981. It is named in honor of Florence Nightingale (1820-1910), the founder of modern nursing. The 2017 encounter is the closest by this asteroid since 1890 and the closest it will ever be until after 2500. Florence will brighten to ninth magnitude in late August and early September, when it will be visible in small telescopes for several nights as it moves through the constellations Piscis Austrinus, Capricornus, Aquarius and Delphinus. 

Radar has been used to observe hundreds of asteroids. When these small, natural remnants of the formation of the solar system pass relatively close to Earth, deep space radar is a powerful technique for studying their sizes, shapes, rotation, surface features and roughness, and for more precise determination of their orbital path.

JPL manages and operates NASA's Deep Space Network, including the Goldstone Solar System Radar, and hosts the Center for Near-Earth Object Studies for NASA's Near-Earth Object Observations Program, an element of the Planetary Defense Coordination Office within the agency's Science Mission Directorate.

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A line that connects a planet to the sun sweeps out equal areas in equal times.-physicsknow

The Law of Areas-PhysicsKnow

The orbital radius and angular velocity of the planet in the elliptical orbit will vary. This is shown in the animation: the planet travels faster when closer to the sun, then slower when farther from the sun. Kepler's second law states that the blue sector has constant area.

Kepler-second-law

This is one of Kepler's laws.This empirical law discovered by Kepler arises from conservation of angular momentum. When the planet is closer to the sun, it moves faster, sweeping through a longer path in a given time.

Developing Kepler's Law of Areas-PhysicsKnow Law of Areas: Considering the area of an elliptical orbit, an infinitesemal area element can be expressed as Integrating over r from the focus outward gives So the time rate of change of the area swept out is The velocity is in the plane of the ellipse and can be divided into radial and angular components: Note that the angular component is proportional to the rate of change of area so that Note that the radius r and the angular velocity are perpendicular to each other so that their product is equal to the magnitude of their vector product. But it was shown in the development of the Law of Orbits that this vector product is proportional to the angular momentum L. It was also shown there that the angular momentum L is a constant, so that establishes that the rate of change of area is a constant for all parts of the orbit, the Law of Areas.

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Solar eclipse of August 21, 2017-PhysicsKnow

Solar eclipse of August 21, 2017-PhysicsKnow

Solar eclipse of August 21, 2017-PhysicsKnow

On Monday, August 21, 2017, a total solar eclipse will be visible within a band across the entire contiguous United States. This eclipse will only be visible in other countries as a partial eclipse.

A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the sun for a viewer on Earth. A total solar eclipse occurs when the moon's apparent diameter is larger than the sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometers wide.

The last time a total solar eclipse was visible across the entire contiguous United States was during the June 8, 1918 eclipse, and not since the February 1979 eclipse has a total eclipse been visible from anywhere in the mainland United States. The path of totality will touch 14 states (although a partial eclipse will be visible in all fifty states),  and 16% of the area of the United States. The event will begin on the Oregon coast as a partial eclipse at 9:06 a.m. PDT on August 21, and will end later that day as a partial eclipse along the South Carolina coast at about 4:06 p.m. EDT.

There are expected to be logistical problems with the influx of visitors, especially for smaller communities.There have also been problems with counterfeit eclipse glasses being sold.

Future total solar eclipses will cross the United States in April 2024 (12 states) and August 2045 (10 states), and annular solar eclipses—meaning the apparent size of the Moon is smaller than that of the Sun—will occur in October 2023

 (9 states) and June 2048 (9 states).

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International Space Station astronauts to view the solar eclipse 3 times-PhysicsKnow

solar eclipse-PhysicsKnow

While millions of Americans gather across the country to catch a glimpse of Monday's total solar eclipse, the astronauts aboard the International Space Station will view the event from a much different vantage point.

The ISS crew members are predicted to view both a partial eclipse and the moon's shadow cast on the North American continent as they make three tracks around the planet 400 km above Earth's surface, according to NASA.

"Observing a total solar eclipse from manned spacecraft is difficult though not impossible," NASA reported.

NASA said the different rates of speed and intersecting paths are the main challenge to viewing an eclipse from space.

At minimum, ISS spends less than 15 seconds traversing the 100-km-wide lunar shadow even when the paths align in space and time, according to NASA. However, Earth’s horizon extends nearly 2,300 km from the ISS, allowing astronauts to see the lunar shadow if they are close enough during the event.

The total eclipse will begin on the Oregon coast at 17:15 UT (10:15 a.m. PDT) and will end along the South Carolina coast at 18:49 UT (2:49 p.m. EDT).

As the space station makes its first pass during the eclipse, the crew members will be able to view a partial solar eclipse with approximately 37 percent of the sun covered up, NASA reports.

However, at this point in time, the ISS will not be able to see the umbra, or the darkest part of the moon's shadow on the Earth's surface. The space station will pass over the western United States and southeastern Canada in the first pass. The total portion of the eclipse will not have started yet for the Earth.

As the station makes its second pass through the moon's shadow, the partial eclipse will be visible to the astronauts with 44 percent of the sun covered.

"ISS will witness the moon’s umbra moving from southwestern Kentucky to northern Tennessee during a portion of this pass," NASA reports.

"The moon’s umbra is visible on the Earth from ISS’s viewpoint while ISS traverses from southern Canada just north of the Montana-Canada border to the Gulf of Saint Lawrence."

At its closest approach, the space station will be making its way south of the Hudson Bay, far removed from the moon's umbra, which will be passing over southwestern Kentucky nearly 1,700 km away.

However, despite the distance, crew members aboard the ISS should still be able to view the shadow near the horizon.

The third pass for the ISS will bring another view of a partial solar eclipse with 85 percent coverage just minutes before orbital sunset. At this point, the darkest part of the lunar shadow will no longer be visible to crew as the umbra will have lifted from the Earth's surface as it makes its transit.

"Because of atmospheric friction and other ISS activities, the orbits undergo small changes from week to week," NASA reports.

The most precise timing will be available on NASA's ISS observations website.

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Biography of Neil Armstrong-physicsknow

Biography of Neil Armstrong

Neil A. Armstrong, the first man to walk on the moon, was born in Wapakoneta, Ohio,

August 5, 1930. He began his NASA career in Ohio.

After serving as a naval aviator from 1949 to 1952, Armstrong joined the National Advisory Committee for Aeronautics (NACA) in 1955. His first assignment was with the NACA Lewis Research Center (now NASA Glenn) in Cleveland. Over the next 17 years, he was an engineer, test pilot, astronaut and administrator for NACA and its successor agency, the National Aeronautics and Space Administration (NASA).

As a research pilot at NASA's Flight Research Center, Edwards, Calif., he was a project pilot on many pioneering high speed aircraft, including the well known, 4000-mph X-15. He has flown over 200 different models of aircraft, including jets, rockets, helicopters and gliders.

Armstrong transferred to astronaut status in 1962. He was assigned as command pilot for the Gemini 8 mission. Gemini 8 was launched on March 16, 1966, and Armstrong performed the first successful docking of two vehicles in space.


As spacecraft commander for Apollo 11, the first manned lunar landing mission, Armstrong gained the distinction of being the first man to land a craft on the moon and first to step on its surface.

Armstrong subsequently held the position of Deputy Associate Administrator for Aeronautics, NASA Headquarters, Washington, D.C. In this position, he was responsible for the coordination and management of overall NASA research and technology work related to aeronautics.

He was Professor of Aerospace Engineering at the University of Cincinnati between 1971-1979. During the years 1982-1992, Armstrong was chairman of Computing Technologies for Aviation, Inc., Charlottesville, Va.

He received a Bachelor of Science Degree in Aeronautical Engineering from Purdue University and a Master of Science in Aerospace Engineering from the University of Southern California. He holds honorary doctorates from a number of universities.

Armstrong was a Fellow of the Society of Experimental Test Pilots and the Royal Aeronautical Society; Honorary Fellow of the American Institute of Aeronautics and Astronautics, and the International Astronautics Federation.

He was a member of the National Academy of Engineering and the Academy of the Kingdom of Morocco. He served as a member of the National Commission on Space (1985-1986), as Vice-Chairman of the Presidential Commission on the Space Shuttle Challenger Accident (1986), and as Chairman of the Presidential Advisory Committee for the Peace Corps (1971-1973).

Armstrong was decorated by 17 countries. He was the recipient of many special honors, including the Presidential Medal of Freedom; the Congressional Gold Medal; the Congressional Space Medal of Honor; the Explorers Club Medal; the Robert H. Goddard Memorial Trophy; the NASA Distinguished Service Medal; the Harmon International Aviation Trophy; the Royal Geographic Society's Gold Medal; the Federation Aeronautique Internationale's Gold Space Medal; the American Astronautical Society Flight Achievement Award; the Robert J. Collier Trophy; the AIAA Astronautics Award; the Octave Chanute Award; and the John J. Montgomery Award.

Armstrong passed away on Aug. 25, 2012 following complications resulting from cardiovascular procedures. He was 82.

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physicsknow- Vacuum and Effects on humans and animals

physicsknow- Vacuum and Effects on humans and animals

Vacuum is space void of matter. The word stems from the Latin adjective vacuus for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure.Physicists often discuss ideal test results that would occur in a perfect vacuum, which they sometimes simply call "vacuum" or free space, and use the term partial vacuum to refer to an actual imperfect vacuum as one might have in a laboratory or in space. In engineering and applied physics on the other hand, vacuum refers to any space in which the pressure is lower than atmospheric pressure.The Latin term in vacuo is used to describe an object that is surrounded by a vacuum.

An_Experiment_on_a_Bird_in_an_Air_Pump_by_Joseph_Wright_of_Derby,_1768

An_Experiment_on_a_Bird_in_an_Air_Pump_by_Joseph_Wright_of_Derby,_1768

Humans and animals exposed to vacuum will lose consciousness after a few seconds and die of hypoxia within minutes, but the symptoms are not nearly as graphic as commonly depicted in media and popular culture. The reduction in pressure lowers the temperature at which blood and other body fluids boil, but the elastic pressure of blood vessels ensures that this boiling point remains above the internal body temperature of 37 °C. Although the blood will not boil, the formation of gas bubbles in bodily fluids at reduced pressures, known as ebullism, is still a concern. The gas may bloat the body to twice its normal size and slow circulation, but tissues are elastic and porous enough to prevent rupture. Swelling and ebullism can be restrained by containment in a flight suit. Shuttleastronauts wore a fitted elastic garment called the Crew Altitude Protection Suit (CAPS) which prevents ebullism at pressures as low as 2 kPa (15 Torr).Rapid boiling will cool the skin and create frost, particularly in the mouth, but this is not a significant hazard.

Animal experiments show that rapid and complete recovery is normal for exposures shorter than 90 seconds, while longer full-body exposures are fatal and resuscitation has never been successful. A study by NASA on eight chimpanzees found all of them survived two and a half minute exposures to vacuum. There is only a limited amount of data available from human accidents, but it is consistent with animal data. Limbs may be exposed for much longer if breathing is not impaired.Robert Boyle was the first to show in 1660 that vacuum is lethal to small animals.

An experiment indicates that plants are able to survive in a low pressure environment (1.5 kPa) for about 30 minutes.

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Eva Ekeblad-First woman in the Royal Swedish Academy of Sciences-physicsknow

Eva Ekeblad

Eva Ekeblad

Eva Ekeblad
Born	July 10, 1724 Stockholm, Sweden
Died	May 15, 1786 (1786-05-16) (aged 61) Skaraborg County, Sweden
Residence	Stockholm and Västergötland
Citizenship	Swedish
Fields	Agronomy
Known for	Making alcohol of potatoes (1746)
Influenced	Reduced hunger by making potatoes a basic food.
Notable awards	Membership in the Royal Swedish Academy of Sciences (1748)
Notes
First woman in the Royal Swedish Academy of Sciences: full member 1748–51, honorary member 1751-86.

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India planted 66 million trees in 12 hours to make India green again- physicsknow

India promised to increase forest cover to 95 million hectares by 2030

 

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Astronomy Highlights in Summer 2017- physicsknow

you can also follow on twitter for physics knowing @physicsknow

https://twitter.com/physicsknow/status/882854732183851008

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The Unsung Heroes of Science - physicsknow

The Unsung Heroes of Science-physicsknow

Some scientists never got the praise they deserved. Here's to the ones history passed over.

1. Alhazen: Method Man

Alhazen: Method Man

 Observe. Hypothesize. Experiment. Revise. Repeat. The scientific method is the foundation upon which researchers build. The man who laid the groundwork for it, however, is all but forgotten in the West.

Born in the mid-10th century in what is now Iraq, Ibn al-Haytham, known to English speakers as Alhazen, was a man of endless curiosity. At a time when the Arabic-speaking world was the epicenter of scientific inquiry, Alhazen was one of its brightest stars.

He wrote more than 100 books on physics, mathematics and astronomy, among other fields, and is believed to be the first to explain how our brains create the illusion of the moon appearing larger near the horizon. His pioneering work on optics inspired the likes of Roger Bacon and Johannes Kepler centuries later. But Alhazen’s creation of the scientific method is his most far-reaching achievement.

Known for developing theories based on experimentation and data collection rather than abstract thought, Alhazen stressed the need to test results — especially those considered canon, as he wrote in his Doubts Against Ptolemy:

“A person who studies scientific books with a view of knowing the real facts ought to turn himself into an opponent of everything that he studies; he should thoroughly assess its main as well as its margin parts, and oppose it from every point of view and in all its aspects.. . . If he takes this course, the real facts will be revealed to him.”

Alhazen’s advice can be seen in action today around the world, from middle school science fairs to the Large Hadron Collider.

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ISRO to launch 3 satellites in 18 months for high-speed internet-physicsknow

ISRO to launch 3 satellites in 18 months for high-speed internet: GSAT-19 launch in June

The GSAT-19 satellite is scheduled to take off in early June onboard GSLV-Mk III, ISRO's heaviest rocket, from SDSC SHAR, Sriharikota. 

 Space Research Organisation (ISRO)  -physicsknowNew Delhi: The Indian Space Research Organisation (ISRO) will send a series of three communication satellites - GSAT-19, GSAT-11 and GSAT-20 – into the orbit in the next 18 months to increase internet speed across the nation, as per a report in Indian Express.

The GSAT satellites are India's indigenously developed technologies of communications satellites, with an objective to make the country self-reliant in broadcasting services.

The GSAT-19 satellite is scheduled to take off in early June onboard GSLV-Mk III, ISRO's heaviest rocket, from SDSC SHAR, Sriharikota.

This would be the maiden flight for GSLV-Mk III, the next generation launch vehicle of ISRO capable of launching 4 ton class of satellites to Geosynchronous Transfer orbit (GTO).

“The next big launch will be GSAT-19 in June. With this launch, we will begin a new age of communication satellites. It is also the beginning of high-throughput satellites (in India),” Tapan Misra, director of Ahmedabad-based Space Applications Centre (SAC), an arm of ISRO that develops satellite payloads, was quoted as saying by the Indian Express.

“While the world is already witnessing a change in the communication technology where voice and video communications are taking place through Internet, with future launches, television will be viewed through Internet using wireless Technology,” Misra added.

These launches will not only revolutionise the way we use televisions and smart-phones, but will also drive the future communication needs of smart cities, the report added.

ISRO said the satellite will carry Ka-band and Ku-band payload along with a Geostationary Radiation Spectrometer (GRASP) payload to monitor and study the nature of the charged particles and influence of space radiation on spacecraft and electronic components.

GSAT-19 satellite will employ advanced spacecraft technologies including bus subsystem, indigenous Li ion battery, indigenous Bus bars for power distribution, etc, the Indian space agency added.

Earlier this month on the 5th May, ISRO successfully launched the Geostationary communication satellite-9 (GSAT-9) – India's gift to South Asia - into a Geostationary orbit.

The GSAT-9 is meant for providing communication and disaster support and connectivity among the countries of South Asia region, with the mission life of about 12 years.

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NASA probes detect man-made bubble around Earth-physicsknow

The impact of such communications extend out beyond our atmosphere, creating a bubble surrounding Earth, NASA`s Van Allen Probes, which study electrons and ions in the near-Earth environment, have revealed. 

Washington: Humans have long been shaping Earth`s landscape, but now scientists know that we also can shape our near-space environment with radio communications.

The impact of such communications extend out beyond our atmosphere, creating a bubble surrounding Earth, NASA`s Van Allen Probes, which study electrons and ions in the near-Earth environment, have revealed. 

A certain type of communications -- very low frequency, or VLF, radio communications -- were found to interact with particles in space, affecting how and where they move. 

At times, these interactions can create a barrier around Earth against natural high energy particle radiation in space, showed the results of a study published in the journal Space Science Reviews.

"A number of experiments and observations have figured out that, under the right conditions, radio communications signals in the VLF frequency range can in fact affect the properties of the high-energy radiation environment around the Earth," said Phil Erickson, Assistant Director at the Massachusetts Institute of Technology (MIT) Haystack Observatory, Westford, Massachusetts.

VLF signals are transmitted from ground stations at huge powers to communicate with submarines deep in the ocean. 

While these waves are intended for communications below the surface, they also extend out beyond our atmosphere, shrouding Earth in a VLF bubble. 

This bubble is even seen by spacecraft high above Earth`s surface, such as NASA`s Van Allen Probes.

The probes noticed an interesting coincidence ? the outward extent of the VLF bubble corresponds almost exactly to the inner edge of the Van Allen radiation belts, a layer of charged particles held in place by Earth`s magnetic fields. 

With further study, VLF transmissions may serve as a way to remove excess radiation from the near-Earth environment. 

Plans are already underway to test VLF transmissions in the upper atmosphere to see if they could remove excess charged particles ? which can appear during periods of intense space weather, such as when the sun erupts with giant clouds of particles and energy, NASA said.

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physicsknow - Earth 2.0 has water, supports alien life?

Earth 2.0 has water, supports alien life?

Proxima B was discovered last August

An ‘Earth-like’ planet orbiting our closest neighbouring star, Proxima Centauri, about 4.2 light years away may have water and the potential to support alien life, a new study has found.

The planet Proxima B was discovered in August last year, and is thought to be of similar size to Earth, creating the possibility that it could have an ‘Earth-like’ atmosphere.

Scientists from the University of Exeter in the U.K. have embarked on their first, tentative steps to explore the potential climate of the exoplanet.

Early studies have suggested that the planet is in the habitable zone of its star Proxima Centauri — the region where, given an Earth-like atmosphere and suitable structure, it would receive the right amount of light to sustain liquid water on its surface.

Now, experts have undertaken new research to explore the potential climate of the planet, towards the longer term goal of revealing whether it has the potential to support life.

Researchers simulated the climate of Proxima B if it were to have a similar atmospheric composition to our own Earth.

The team also explored a much simpler atmosphere, comprising of nitrogen with traces of carbon dioxide, as well as variations of the planets orbit. This allowed them to both compare with, and extend beyond, previous studies.

However, much more work must be done to truly understand whether this planet can support, or indeed does support life of some form, researchers said.

“Our research team looked at a number of different scenarios for the planet’s likely orbital configuration using a set of simulations,” said Ian Boutle, lead author of the study published in the journal Astronomy and Astrophysics.

“One of the main features that distinguishes this planet from Earth is that the light from its star is mostly in the near infra-red,” said James Manners, from University of Exeter.

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physicsknow - Mark Elliot Zuckerberg computer programmer who was co founder and CEO of Facebook

Mark Zuckerberg -physicsknow
Born May 14, 1984

Mark Elliot Zuckerberg computer programmer who was cofounder and CEO of Facebook, a social networking Web site.

After attending Phillips Exeter Academy, Zuckerberg enrolled at Harvard University in 2002. On February 4, 2004, he launched thefacebook.com(renamed Facebook in 2005), a directory in which fellow Harvard students entered their own information and photos into a template that he had devised. Within two weeks half of the student body had signed up. Zuckerberg’s roommates, Dustin Moskovitz and Chris Hughes, helped him add features and make the site available to other campuses across the country. Facebook quickly became popular as registered users could create profiles, upload photos and other media, and keep in touch with friends. It differed from other social networking sites, however, in its emphasis on real names (and e-mail addresses), or “trusted connections.” It also laid particular emphasis on networking, with information disseminated not only to each individual’s network of friends but also to friends of friends—what Zuckerberg called the “social graph.”

In the summer of 2004 the trio moved their headquarters to Palo Alto, California, where Zuckerberg talked venture capitalist Peter Thiel into giving them seed money. Zuckerberg dropped out of Harvard to concentrate on the fledgling company, of which he became CEO and president. In May 2005 Facebook received its first major infusion of venture capital ($12.7 million). Four months later Facebook opened to registration by high-school students. Meanwhile, foreign colleges and universities also began to sign up, and by September 2006 anyone with an e-mail address could join a regional network based on where he or she lived. About that time Zuckerberg turned down a $1 billion buyout offer from Yahoo!, but in 2007 Facebook struck a deal with Microsoft in which the software company paid $240 million for a 1.6 percent stake in Facebook; two years later Digital Sky Technologies purchased a 1.96 percent share for $200 million. In 2008 Zuckerberg’s new worth was estimated at about $1.5 billion. After Facebook’s initial public offering (IPO) of stock in 2012, Zuckerberg’s net worth was estimated at more than $19 billion. In April 2017 his net worth is 59.4 billion. Now monthly Facebook has 1 billion active users.

Nevertheless, Zuckerberg has remained true to his initial vision – to create a website that the entire world can use to communicate openly and easily with one another. Hes turned down opportunities to sell the site, often for multi-billion dollar sums. Hes even turned down chances to increase the sites income from ad revenue, instead preferring to keep the user experience clean and pure.The end result is one of the worlds biggest online businesses, and an icon of the tech renaissance thats occurred recently.Although its true value is debatable, its safe to say that Facebook, and its creator Mark Zuckerberg, are two of the twenty-first centurys most influential, controversial, and potentially powerful figures.

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the father of X-Rays and diagnostic radiology!-physicsknow

Who was the first person ever to receive the Nobel Prize in Physics? Wilhelm Röntgen, the father of X-Rays and diagnostic radiology! He was born #onthisday in 1845.

physicsknow 

Röntgen left his mark on science in a variety of areas, from understanding the behaviour of gases at different temperatures to the compressibility of water. But one of his most famous scientific contributions is the discovery of X-rays.

X-rays are a type of radiation. They have a range of uses, but they are most commonly known for their role in helping doctors see inside of patients’ bodies. Doctors use them to create medical scan images of different body parts, such as broken bones. This helps them diagnose diseases and rule out medical problems safely and rapidly without having to make an incision. You can learn more about X-rays here:

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This Month In Physics History-physicsknow

The Curie Brothers Discover Piezoelectricity  March 1880:physicsknow

Microphones, quartz watches, and inkjet printers all rely on an unusual phenomenon known as the piezoelectric effect found in various crystals, ceramics, and even bone. It was discovered by none other than French physicist Pierre Curie, working with his older brother Jacq

Brothers and colleagues: Jacques (left) and Pierre (right) Curie, discoverers of the piezoelectric effect.

ues, who found that putting pressure on these materials created electricity (the name comes from piezein — Greek for “squeeze”).
Born in Paris in 1859 to a physician named Eugene Curie, Pierre’s early education was decidedly unorthodox: his father opted for private tutors for his son, believing it to be the best approach given the boy’s temperament and keen intellect. Pierre showed an early aptitude for mathematics, and at 16 entered the Sorbonne for his university studies. He successfully earned the equivalent of a master’s degree by 18, but was forced to postpone his doctoral studies. During this time, he earned a meager living as a lab instructor.
Pierre started conducting chemistry experiments at the age of 20 with Jacques, focusing on the structure of crystals. They were especially interested in the pyroelectric effect, in which a change in temperature in a crystalline material generates an electric potential. This effect had been known since the mid-18th century, thanks to the work of Carl Linnaeus and Franz Aepinus, and subsequent scientists had hypothesized that there could be a relationship between the properties of mechanical stress and electrical potential. But experimental confirmation proved elusive.
The brothers Curie thought there would be a direct correlation between the potential generated by temperature changes and the mechanical strain that gave rise to piezoelectricity. They expected that a piezoelectric effect would arise in materials with certain crystal asymmetries. Armed with the crudest of materials — tinfoil, glue, wire, magnets, and a simple jeweler’s saw — they tested various types of crystals, including quartz, topaz, cane sugar, Rochelle salt, and tourmaline. As a result, the Curies found that when such materials were compressed, the mechanical strain did indeed result in an electric potential. The strongest piezeoelectric effects were found in quartz and Rochelle salt. The brothers put their discovery immediately to good use by inventing the piezoelectric quartz electrometer.
There was a twist to the piezoelectric saga still to come. The following year, mathematician Gabriel Lippman demonstrated that there should be a converse piezoelectric effect, whereby applying an electric field to a crystal should cause that material to deform in response. The brothers rushed to test Lippman’s theory, and their experiments showed the mathematician was correct. Piezoelectricity could indeed work in the other direction.
After the initial flurry of excitement died down, piezoelectric research faded into the background for the next 30 years or so, in part because the theory was so mathematically complex. But incremental progress was still being made. In 1910, Woldemar Voigt published the definitive treatise on the subject, Lehrbuch der Kristallphysik, a massive tome describing the 20-odd classes of natural crystal with piezoelectric properties. More importantly, it rigorously defined the 18 possible macroscopic piezoelectric coefficients in crystal solids.
This set the stage for subsequent development of practical applications for such materials, beginning with sonar in 1917, when Paul Langevin developed an ultrasonic transducer for use on submarines using thin quartz crystals. Many automobiles today have ultrasonic transducers to assist drivers in measuring the distance between the rear bumper and any obstacles in its path.
Pierre moved on to investigating magnetism, uncovering an intriguing effect of temperature on paramagnetism now known as Curie’s law. Another discovery was the Curie point: the critical temperature at which ferromagnetic materials cease to be ferromagnetic. He even flirted with paranormal spiritualism as the 19th century drew to a close, attending séances with famed medium Eusapia Palladino, approaching them as a scientific experiment with detailed observational notes, in hopes that such study would shed light on magnetism. “I must admit that those spiritual phenomena intensely interest me,” he wrote to his fiancée, Marie Sklodowska, in 1894. “I think in them are questions that deal with physics.”
Pierre married Marie the following year, when he also finally completed his doctorate, thanks to her encouraging him to use his magnetism work as a doctoral thesis. He became a professor of physics and chemistry at Paris in 1895. (Jacques became a professor of mineralogy at the University of Montpellier.) His new wife replaced his brother as his scientific partner. The two discovered radium (and later, polonium), sharing the 1903 Nobel Prize in Physics with Henri Becquerel. The piezoelectric quartz electrometer invented by Pierre and Jacques all those years before proved an essential instrument in their ongoing work.
Towards the end of his life, Pierre showed early signs of over-exposure to radium. In fact, his clothes were often so radioactive he had to postpone experiments by several hours because it interfered with his instruments. The unit of radioactivity is called the curie in his and Marie’s honor. But he was spared a gruesome death by radiation sickness. Instead, he was killed in a freak accident, run down by a wagon on the Place Dauphine as he was crossing the busy street.
Marie always felt Pierre did not get the respect and support he deserved from his scientific colleagues. He did not engage in academic politics, preferring to focus on his research. He was rejected for a professorship in mineralogy and denied membership in the French Academy in 1903, the same year he won the Nobel Prize. His early work on piezoelectricity was not, perhaps, his most significant discovery over his illustrious career, but as he observed in an 1894 letter to Marie: “[In science] we can aspire to accomplish something…. every discovery, however small, is a permanent gain.”

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Bihar Diwas: Did You Know Its Origins Lie In The Raj Era?-physicsknow

On 22 March, the 105th Bihar Diwas will be observed, setting the stage for three-day-long celebrations in the state. A string of events, including performances by Bollywood personalities, and announcement of big-ticket government initiatives will mark the occasion. But why is Bihar Diwas celebrated and which event does it commemorate? The answer lies in history, in the dying days of the British Raj.

22 March 1912

The coronation of King George V in Delhi took place in 1911. It was decided that the capital of British India was shifting to Delhi. The new governor of Bengal Thomas-Gibson Carmichael, who took charge on 21 March 1912, wasted no time in announcing the next day that the Bengal Presidency will, from then on, be split into the four subhas of Bengal, Orissa, Bihar and Assam.
Thomas -Gibson Carmichael .

Why Were They Clubbed Together Earlier?

The Battle of Buxar was fought on 22 October 1764 between the forces under the command of the British East India Company led by Hector Munro, and the combined army of Mir Qasim, the Nawab of Bengal; the Nawab of Awadh; and the Mughal King Shah Alam II. The battle fought at Buxar, a "small fortified town" within the territory of Bengal, located on the bank of the Ganges about 130 km west of Patna, was a decisive victory for the British East India Company.
Date: 22 October 1764; Location: Near Buxar. The Commanders and leaders are: Shuja-ud-Daula, Mirza Najaf Khan, Shah Alam II, Mir Qasim, Hector Munro of Novar.

Diwani Rights Go to East India Company

After the Battle of Buxar in 1764, which was fought in Buxar, hardly 115 km from Patna, the Mughals as well as the Nawabs of Bengal lost effective control over the territories, then constituting the province of Bengal, which currently comprises Bangladesh, and the Indian states of West Bengal, Bihar, Jharkhand, Odisha. East India Company was accorded the diwani rights, that is, the right to administer the collection and management of revenues of the province of Bengal.
India’s political map in 1765, the year the decisive battle of Buxar was fought.

Nitish Kumar’s Brainchild: Bihar Diwas From 2010

When Nitish Kumar took charge as the chief minister of Bihar, he was looking for a commemorative event in Bihar’s history that could become the state’s official day of celebration. The fact that Bihar had been carved out from Bengal Presidency on 22 March 1912, was now the birthday of Bihar. Ever since then, the day is celebrated across the state as Bihar Diwas. Numerous state functions and children’s activities are held on this day. We wish Bihar a Happy Bihar Diwas.

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