Professor Jorge Rocca offer a new path to creating the extreme conditions found in stars, using ultra-short laser pulses irradiating nanowires

Representation of the creation of ultra-high energy density matter by an intense laser pulse irradiation of an array of aligned nanowires. Credit: R. Hollinger and A. Beardall

The energy density contained in the center of a star is higher than we can imagine -- many billions of atmospheres, compared with the 1 atmosphere of pressure we live with here on Earth's surface.

These extreme conditions can only be recreated in the laboratory through fusion experiments with the world's largest lasers, which are the size of stadiums. Now, scientists have conducted an experiment at Colorado State University that offers a new path to creating such extreme conditions, with much smaller, compact lasers that use ultra-short laser pulses irradiating arrays of aligned nanowires.

The experiments, led by University Distinguished Professor Jorge Rocca in the Departments of Electrical and Computer Engineering and Physics, accurately measured how deeply these extreme energies penetrate the nanostructures. These measurements were made by monitoring the characteristic X-rays emitted from the nanowire array, in which the material composition changes with depth.

HPLSE editorial tribute to Professor David Neely

OPN Talks with Jorge Rocca photo: Optics & Photonics News

Numerical models validated by the experiments predict that increasing irradiation intensities to the highest levels made possible by today's ultrafast lasers could generate pressures to surpass those in the center of our sun.

J. J. Rocca's research works Colorado State ResearchGate

The results, published Jan. 11 in the journal Science Advances, open a path to obtaining unprecedented pressures in the laboratory with compact lasers. The work could open new inquiry into high energy density physics; how highly charged atoms behave in dense plasmas; and how light propagates at ultrahigh pressures, temperatures, and densities.

Creating matter in the ultra-high energy density regime could inform the study of laser-driven fusion -- using lasers to drive controlled nuclear fusion reactions -- and to further understanding of atomic processes in astrophysical and extreme laboratory environments.

A strategy to achieve ultrahigh power and energy density in lithium-ion batteries Tech Xplore

The ability to create ultra-high energy density matter using smaller facilities is thus of great interest for making these extreme plasma regimes more accessible for fundamental studies and applications. One such application is the efficient conversion of optical laser light into bright flashes of X-rays.

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The above post is reprinted from materials provided by Sciencedaily. Note: Materials may be edited for content and length.

2017 in Review: NASA’s Space Technology Mission Directorate (STMD) Pioneering Progress

Solar Electric Propulsion work is underway, sponsored by NASA's Space Technology Mission Directorate and managed by NASA's Glenn Research Center. A prototype 13-kilowatt Hall thruster, shown here, is tested to demonstrate the technology readiness needed for industry to continue the development of high-power solar electric propulsion into a flight-qualified system. Credits: NASA

NASA’s Space Technology Mission Directorate (STMD) is dedicated to pushing the technological envelope, taking on challenges not only to further space agency missions near Earth, but also to sustain future deep space exploration activities.

“In 2016, we completed several major program milestones,” explains Steve Jurczyk, NASA associate administrator for STMD.

During the year, STMD focused upon and made significant progress in advancing technologies and capabilities in the following areas:

Space Power and Propulsion;

• High-Bandwidth Communications, Deep Space Navigation, Avionics;
• Advanced Life Support and Resource Utilization;
• Entry, Descent and Landing Systems;
• Autonomy and Space Robotic Systems;
• Lightweight Structures and Manufacturing;
• Space Observatory Systems

Enabling engine 

Jurczyk points to areas of notable progress in fiscal year 2016, particularly work on high-power Solar Electric Propulsion (SEP) – an enabler for cost-effective deep space exploration.

Asteroid Redirect Mission makes use of solar electric propulsion. The vehicle’s solar arrays collect power from the sun and convert it to energy to ionize and accelerate xenon propellant, resulting in the bright blue plume at the rear of the vehicle. Credits: NASA

SEP makes use of large solar cell arrays that convert collected sunlight energy to electrical power. That energy is fed into extremely fuel-efficient thrusters that provide gentle but nonstop thrust throughout the mission. SEP thrusters are designed to use far less propellant than comparable, conventional chemical propulsion systems.

“We completed the development and testing of a prototype SEP engine at NASA’s Glenn Research Center. Also, we have contracted with Aerojet Rocketdyne to develop the SEP flight system for the Asteroid Redirect Robotic Mission,” Jurczyk notes.

Furthermore, SEP solar array technology is being transitioned into commercial application, Jurczyk adds, by both Space Systems Loral and Orbital ATK.

Green propellant 

Another 2016 spotlight on progress, Jurczyk observes, is the integration and testing of the Green Propellant Infusion Mission (GPIM). Now ready for launch in 2017, GPIM will test the distinctive quality of a high-performance, non-toxic, “green” fuel in orbit.

STMD worked with Aerojet Rocketdyne in Redmond, Washington and GPIM prime contractor Ball Aerospace & Technologies Corp. in Boulder, Colorado, to develop the spacecraft capable of using the unique propellant. It will fly on the U.S. Air Force’s Space Test Program (STP-2) mission.

Given the term “green” propellant, Jurczyk points out that the Air Force-developed fuel is a hydroxyl ammonium nitrate-based fuel/oxidizer mix, also known as AF-M315E. GPIM will flight demonstrate this fuel designed to replace use of highly toxic hydrazine and complex bi-propellant systems now in common use today.

“GPIM’s green propellant is less toxic than hydrazine. It will reduce spacecraft processing costs and it has 40 percent higher performance by volume than hydrazine,” Jurczyk says.

Aerojet Rocketdyne, builder of GPIM’s set of thrusters, is now marketing the novel thrusters as a product. The aerospace firm is also working with NASA’s Glenn Research Center to further enhance the thrusters, looking to reduce cost and add to their reliability, Jurczyk adds. “So we’re collaborating with the aerospace company to further advance this technology and I’m pleased with the progress.”

Push the technology 

Jurczyk reports that STMD-supported work on the Deep Space Atomic Clock, DSAC for short, is ongoing.

DSAC is a small, low-mass atomic clock based on mercury-ion trap technology that will be demonstrated in space, providing unprecedented stability needed for next-generation deep space navigation and radio science. NASA’s Jet Propulsion Laboratory oversees project development of DSAC, which offers the promise of 50 times more accuracy than today’s best navigation clocks.

STMD’s Flight Opportunities program includes use of Masten Space Systems’ XA-0.1B “Xombie” vertical-launch, vertical-landing reusable rocket as a risk-reduction activity, testing science experiments and hardware before long duration spaceflight. Vehicle is shown soaring above Mojave Air and Space Port in California. Credits: NASA Photo/Tom Tschida

The task of designing DSAC has not been trouble-free, but it represents a tenant of STMD “to push the technology,” Jurczyk responds. Taking on the challenges of space-rating terrestrial based atomic clock technology is not easy. However, the path forward has been outlined with launch of DSAC now eyed for next year.

The DSAC demonstration unit and payload is to be hosted on a spacecraft provided by Surrey Satellite Technologies U.S. of Englewood, Colorado, lofted spaceward as part of the U.S. Air Force Space Test Program 2 mission aboard a Space X Falcon 9 Heavy booster.

Tipping point partnerships 

In 2016, STMD entered into their first set of public-private partnerships, a solicitation that proved very beneficial – to both industry and NASA. Called “Utilizing Public-Private Partnerships to Advance Tipping Point Technologies,” Jurczyk is pleased with this facilitated collaborative effort with industry. These partnerships require companies to contribute at least 25 percent of the funding; NASA contributes up to $20 million for ground-based efforts.

With the recent increase of the U.S. private sector interest in space applications, NASA is seeking commercial space technologies that are at a “tipping point” in their development.

“We do many one-on-one discussions with companies about their interests. For NASA, we want to help advance technologies that boost commercial products and services,” he points out. The Tipping Point partnerships have led to contracts, for example, in space robotic manufacturing and small spacecraft technologies.

Similarly, Jurczyk adds that in 2016, STMD saw collaborative opportunity for industry to tap into NASA expertise, allowing companies to use space agency talent and facilities. This collaboration is made possible through non-reimbursable, no-exchange-of-funds Space Act Agreements. Those types of agreements, he emphasizes, have enabled private-sector advancements in technologies such as small launch vehicle rocket engines and advanced structures for small boosters.

Flight opportunities

“It has been a good and productive year for STMD’s Flight Opportunities program,” Jurczyk advises.

That program provides affordable access to relevant space-like environments for NASA payloads. This activity makes use of a variety of flight platforms, such as Blue Origin’s New Shepard suborbital vehicle, Masten Space Systems’ XA-0.1B “Xombie” vertical-launch, vertical-landing reusable rocket, as well as the UP Aerospace SpaceLoft sounding rocket.

STMD’s lineup of smallsat launches in 2017 includes the CubeSat Proximity Operations Demonstration (CPOD) project that will demonstrate rendezvous, proximity operations and docking using two CubeSats. Credits: NASA/Ames/Tyvak Nano-Satellite Systems, Inc.

“We can ‘ring out’ experiments and technologies in short duration exposure to relevant flight conditions before they go onto longer duration flight on space missions,” Jurczyk explains. “It’s a risk reduction activity,” he continues, for example, in life science research or shaking out various robotic technologies.

Big year ahead 

Looking into 2017, STMD’s Jurczyk highlights the launch of the Green Propellant Infusion Mission and the Deep Space Atomic Clock. “Those are two major flight demonstrations and are very important.”

Among a host of STMD-supported activities, next year will see flight of small satellites to showcase, for instance, optical laser communications. Then there’s the Integrated Solar Array and Reflectarray Antenna (ISARA) for advanced communications and the CubeSat Proximity Operations Demonstration (CPOD). The function of CPOD is to trial-run autonomous rendezvous and docking, Jurczyk says.

“There’s going to be a lot going on,” Jurczyk concludes. “It’ll be a big year for small satellites and space technology.”

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The above post is reprinted from materials provided by NASA. Note: Materials may be edited for content and length.

Total Solar Eclipse 2017: When, Where and How to See It (Safely)

Map showing the path of totality for the Aug. 21, 2017 total solar eclipse. Credit: Fred Espenak/NASA GSFC

On Aug. 21, 2017, American skywatchers will be treated to a rare and spectacular celestial show — the first total solar eclipse visible from the continental United States in nearly four decades.

Next year's "Great American Total Solar Eclipse" will darken skies all the way from Oregon to South Carolina, along a stretch of land about 70 miles (113 kilometers) wide. People who descend upon this "path of totality" for the big event are in for an unforgettable experience, said eclipse expert Jay Pasachoff, an astronomer at Williams College in Massachusetts.

"It's a tremendous opportunity," Pasachoff told Space.com. "It's a chance to see the universe change around you.

A total solar eclipse last darkened soil on the U.S. mainland on Feb. 26, 1979. But August 2017 will mark the first time in 99 years that such an event is "readily available to people from coast to coast," Pasachoff said.

Total Solar Eclipse 2017 Photo: Eclipse2017.org

A rare event

The fact that total solar eclipses occur at all is a quirk of cosmic geometry. The moon orbits an average of 239,000 miles (384,600 kilometers) from Earth — just the right distance to seem the same size in the sky as the much-larger sun

But most solar eclipses are of the partial variety, in which the moon appears to take a bite out of the sun's disk. Indeed, two to five solar eclipses occur every year on average; total eclipses happen just once every 18 months or so. (Eclipses are relatively rare because the moon's orbit is inclined about 5 degrees relative to that of Earth. If the two bodies orbited in exactly the same plane, a solar eclipse would occur every month, during the moon's "new" phase.)

How Solar Eclipses Work: When the moon covers up the sun, skywatchers delight in the opportunity to see a rare spectacle. See how solar eclipses occur in this Space.com infographic. Credit: Karl Tate, SPACE.com Contributor

Furthermore, the narrow path of totality is often inaccessible to skywatchers — most of Earth is covered by water, after all — so a total solar eclipse that occurs over populated areas is quite special. Indeed, the August 2017 event will be the first one whose totality path lies completely within the United States since 1776, experts have said.

That path goes from the Oregon coast through Idaho, Wyoming, Nebraska, Kansas, Missouri, Illinois, Kentucky, Tennessee, Georgia, North Carolina and South Carolina. While just 12 million people or so live within the narrow band, perhaps 220 million reside within a day's drive of it, according to Space.com skywatching columnist Joe Rao. [Incredible Solar Eclipse View Shot During Alaska Airlines Flight (Video)]

Pasachoff advises folks to make that drive when the time comes.

"Though the rest of the continental U.S. will have at least a 55 percent partial eclipse, it won’t ever get dark there, and eye-protection filters would have to be used at all times even to know that the eclipse is happening. The dramatic effects occur only for those in the path of totality," Pasachoff said in a statement.

"If you are in that path of totality, you are seeing the main event, but if you are off to the side — even where the sun is 99 percent covered by the moon — it is like going up to the ticket booth of a baseball or football stadium but not going inside," he added.

Pasachoff himself plans to be there. He has observed 63 solar eclipses to date, and not just for fun: The events provide a rare opportunity to study the sun's wispy outer atmosphere, which is called the corona. (The sun's overwhelming brightness usually drowns out the faint corona.)

Temperatures in the corona top 1.8 million degrees Fahrenheit (1 million degrees Celsius), making the region much hotter than the solar surface, which is just 11,000 degrees F (6,000 degrees C) or so. How the corona gets so hot has puzzled scientists for decades, and Pasachoff and his colleagues aim to gather some useful data during the Great American Eclipse.

"How energy is injected into the corona is one of the things we'll be investigating," Pasachoff told Space.com.


Be safe!

If you do plan to observe the August 2017 eclipse, remember: NEVER look directly at the sun without proper eye protection, except when the solar disk is completely occluded (during the brief period of totality); serious and permanent eye damage can result.

"Proper eye protection" includes specially made solar filters, eclipse glasses or No. 14 welder's glass. You can also observe the eclipse indirectly, by making a pinhole camera or watching shadows cast by trees. (The gaps between leaves act as natural pinholes.)

You should never look directly at the sun, but there are ways to safely observe an eclipse. See how to safely observe a solar eclipse with this Space.com infographic. Credit: Karl Tate, SPACE.com Contributor

To learn more about how to safely observe the sun, check out this Space.com infographic.

Safely See the Sun – Build a Shoebox Pinhole Camera


Finally, if you miss out on the August 2017 event, don't despair — you'll get another chance seven years later. In 2024, a total solar eclipse will darken the skies above Mexico and Texas, up through the Midwest and northeastern U.S

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The above post is reprinted from materials provided by Space. Note: Materials may be edited for content and length.

A famous physicist demonstrated that the 2015 Nobel Prize for Physics was awarded to the wrong person

2015 Nobel Prize for Physics was awarded for the discovery of  (neutrino oscillations) through which it is proved that neutrinos have mass. 

The report does not claim the prize holders deserved or not that research was flawed, the physicist argues that the way the commission interpreted discovery is wrong. The award was given for research into neutrinos, particles (phantom) which appear from nuclear interaction as well as the center of the sun.

Japanese Physicist Wins 2015 Nobel Prize For Neutrino Research

They are described as (ghost particles) because rarely interact with matter. The only way that scientists can detect the presence of neutrinos is through their interaction with subatomic weak forces and gravity, using Super-Kamiokande detector and the detector particles from Japan or Neutrino Sudbury Observatory (SNO) in Canada.

SNO detector installed underground, before cabling the photomultiplier tubes. (Courtesy of SNO) photo: wikipedia

Experts have discovered that there are three types of neutrinos - electronic, muon and taonic. A neutrino can become electronic or taonic, this process is called oscillation. Super-K detector that can detect muon neutrinos generated only by cosmic rays hitting the Earth's atmosphere, it revealed that the Earth is hit much more atmospheric neutrinos at the surface than in its interior. This phenomenon suggests that neutrinos oscillated while penetrated the atmosphere Super-K detector because he could not detect.



SNO detector team used in 2001 and 2002 for observation of the Sun neutrinos. One of their techniques can only detect electrons, neutrino and another method to detect all three types. The results showed that when the neutrino electron reached Earth, only 34% of them remained electrons neutrino, which means that over time changed their shape.

Nobel Committee for Physics interpreted these results as evidence that neutrinos can oscillate while traveling and finally they have mass.

Alexei Smirnov physicist from Max Planck Institute for Nuclear Physics in Germany stated in his work that the committee members have used the wrong word (oscillation). 

He believes the Japanese team successfully proved oscillation action, but the team that used the SNO detector proved what was happening to the neutrinos from the Sun, more subtle change.

Physicist Awarded Einstein Medal ICTP

photo: taringa.net

Smirnov believes that neutrinos from the Sun change its type, but not through oscillations as Nobel committee members have understood.


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Astronomer who rewrote the history of the Universe. He originally wanted to be a priest. Later, his mother had suffered from Church

The Great Comet of 1577, which Kepler witnessed as a child, attracted the attention of astronomers across Europe photo: wikipedia

December 27, 1571 was born Johannes Kepler, astronomer and astrologer, who discovered that the Earth and the planets move around the sun in an elliptical orbit (d. November 15, 1630)

Kepler was born  in Weil der Stadt, Württemberg, Germany, and studied since 1591 theology at the University of Tübingen. One of his teachers was Michael Maestlin, defender of the heliocentric theory of Copernicus. 

Michael Maestlin - Wikipedia

Kepler wanted to be a priest, a Protestant, but finally, with great penchant for math function supports 1594 teacher of mathematics and astronomy at the University of Graz, Austria. Here are working on a complex geometrical hypotheses aimed at explaining the remoteness of the orbits of the five planets known at that time (Mercury, Venus, Mars, Jupiter and Saturn).

University of Tübingen Britannica

Kepler was a German mathematician and optician. photo: wikipedia

Kepler believes that the sun exerts a force that decreases in proportion to the removal of a planet: "Planets move accordingly on an elliptical path, the center of which is the sun." Thus states the first law of planetary motion (see Kepler's Laws), published in "Mysterium Cosmographicum" ( "The Mystery of cosmic world", 1596).

In April 1597, Kepler married Barbara Mühlek. Due to pressure from the Catholic Counter-Reformation, Kepler is forced to leave Graz and in 1600 accepted the offer to work in Prague as an assistant to Tycho Brahe, the astronomer court Emperor Rudolf II.

Rudolf II, Holy Roman Emperor - Wikipedia

The Galileo Project

The qualities of Tycho Brahe's observatory are now complemented with exceptional knowledge of mathematics of Kepler. After the death of Brahe in 1601, Kepler became his successor as imperial mathematician and astronomer. 

Kepler observed 1604 "Supernova 1604" and published his observations in his "De Stella Nova in Serpentarii Pede" ( "About a new star in the constellation foot serpent"). In "Astronomia Nova" ( "New Astronomy", 1609) publishes research results on the ellipse Mars and the second law states: "The planet is closer to the sun, the faster it moves." 

Remnant of Kepler's Supernova SN 1604 photo: wikipedia

In 1612 Kepler is set at Linz in Austria, where his work appears "Harmonices Mundi" ( "Harmony of the World", 1619). In the last chapter of this book, based on observations and calculations, sets out the third law of planetary motion: "The square of time of revolution is proportional to the third power of the average distance between a planet and the sun."

In the years 1615-1620 Kepler had to defend his mother, who was accused of witchcraft. He eventually managed to obtain her release, but without being able to prevent the torture was subject, following which she died a year later. Kepler lived in an era of intolerance, struggles between Catholics and Protestants during the Thirty Years' War, was forced repeatedly to flee to escape persecution, although his attempts to remain neutral.

His last major work, published in his lifetime yet is Tabulae Rudolfinae (1627), which contains tables that describe the movements of the planets. It will be the basis for any astronomical for the next 200 years. In his theory of gravitation forces, Isaac Newton relied heavily on Kepler's observations.

Apart works of astronomy, Kepler described a process for determining the volumes on which will develop integral calculus. He also studied symmetry of snowflakes and calculated the natural forces involved in the growth and geometric structures that will be applied in the study of crystallography. He worked in the field of optics, which to remember his invention called "Kepler's telescope."


Johannes Kepler died on November 15, 1630 in Regensburg, Germany, aged 59 years. In his memory, the University of Linz called "Johannes Kepler Universität,".

Invenit Mundo presents major historical significance of the day December 27:

1585 - He died Pierre de Ronsard, the French poet, the main representative of the Pleiades (sixteenth-century French literary school) ( "Ode", "Hymns") (b. September 11, 1524)

1717 - was born Pope Pius VI (d. 1799)

1784 - peasant revolt led by Horea, Closca and Crisan, broke out November 2nd. 1784. Horea and Closca are trapped in the forest in the mountains Scoruşet Gilău, then imprisoned at Alba-Iulia

1806 - Constantine Ypsilanti returns to Bucharest. He organizes an army intended to enable the realization of his plan, establishing a kingdom of Dacia format Moldovan and Romanian Country Serbia

1816 - Held at the initiative of Gheorghe Asachi Iasi first theater performance in Romanian: "Mirtil and Hloe" pastoral in one act

1822 - Louis Pasteur was born chemist and biologist, member of the French Academy; He discovered the nature of infectious diseases of humans and animals and rabies vaccine (applied for the first time in 1885), thereby laying the foundations of immunology; established conservation beer pasteurisation method (d. September 28, 1895)

1831 - Charles Darwin embarked on his historic journey aboard the HMS Beagle royal

1832 - was born Pavel Mikhailovich Tretyakov, Russian critic and humorist, founder of the art gallery that bears his name

1896 - He was born American novelist Louis Bromfield (d. March 18, 1956)

1897 - VIANU Tudor was born, poet, philosopher and esthetician Romanian member of the Romanian Academy; He was director general of the National Commission for UNESCO director general of the Romanian Academy Library, Director of the National Theatre in Bucharest; wrote aesthetic and stylistic studies, memoirs, analyzed in terms of aesthetics Romanian literary phenomenon and universal ( "Art and beauty," "Art Romanian prose writers") (d. May 21, 1964)

1901 - Marlene Dietrich was born, legendary figure of cinema, film actress, theater, music hall, vaudeville singer (movies: "Blue Angel", "stigma of evil") (d. May 6, 1992)

1909 - D.A. Sturdza, due to sickness, withdraws from the party and the leadership of the PNL; I.I.C. Brătianu was appointed prime minister

1925 - He died Sergei Aleksandrovich Yesenin, Russian poet, one of the most sensitive of the village evocators Russian (committed suicide) (n.1895)

1945 - Establishment of the World Bank for Reconstruction and Development and the International Monetary Fund (IMF) as a result of the UN Monetary and Financial Conference in Bretton Woods (1 to 12 July 1945). Romania became a member of the two financial institutions to December 15, 1972

1977 - A Ciucurencu Alexander died, painter, member of the Romanian Academy; In 2003, UNESCO included in the calendar of cultural anniversaries and name Alexander Ciucurencu, marking 100 years since the birth of the painter (b. September 27, 1903)

1978 - In Spain establishes democracy after 40 years of dictatorship

1989 - In the first plenary NSFC was adopted Decree-Law no. 2 on the establishment, organization and functioning of NSFC and territorial councils of the NSF; also he was elected Executive Office of NSFC: President - Ion Iliescu; First Deputy Chairman - Dumitru Mazilu; Vice - Cazimir Ionescu, Karoly Kiraly; Secretary - Dan Martian; members - Teodoriu Bogdan, Vasile Neacsa, Silviu Brucan Manole Gheorghe Ion Caramitru, Nicolae Radu

1991 - It was open to the public, the Cotroceni National Museum, established on July 10, 1991

1995 - The Bosnian government army and Bosnian Serb forces evacuated the key positions on the front lines around Sarajevo

1998 - The European Commission approved the creation of a common bank, based in Vienna, by the third private bank German Dresdner Bank and National Bank of Paris (BNP), which aims to administer the activities of the two institutions in Europe East

2004 - Viktor Yushchenko has claimed victory in the presidential elections in Ukraine


2006 - Finished the former US president Gerald Ford life. He was the only president who was directly elected for the posts of president and vice president of the United States.


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Einstein's Theory Just Put the Brakes on the Sun's Spin

Credit: NASA/SDO

Although the sun is our nearest star, it still hides many secrets. But it seems that one solar conundrum may have been solved and a theory originally proposed in 1905 by Albert Einstein could be at the root of it all.

Nov. 21, 1905: It Was a Very Good Year, If You Were Einstein Wired

Twenty years ago, solar astronomers realized that the uppermost layer of the sun rotates slower than the rest of the sun's interior. This is odd. It is well known the sun rotates faster at its equator than at its poles — a phenomenon known as "differential rotation" that drives the sun's 11-year solar cycle — but the fact that the sun has a sluggish upper layer has been hard to understand. It's as if there's some kind of force trying to hold it in place while the lower layers churn below it.

Solar Rotation Varies by Latitude NASA

Now, researchers from University of Hawaii Institute for Astronomy (IfA), Brazil, and Stanford University may have stumbled on an answer and it could all be down to fundamental physics. It seems that the light our sun generates has a braking effect on the sun's surface layers.


"The sun won't stop spinning anytime soon, but we've discovered that the same solar radiation that heats the Earth is 'braking' the sun because of Einstein's Special Relativity, causing it to gradually slow down, starting from its surface," said Jeff Kuhn, of IfA Maui, in a statement.

Solar Radiation | EM SC 100: First Year Seminar

Special relativity predicts that photons, which carry the electromagnetic force (i.e. light), also carry a tiny amount of momentum. If you have enough photons travelling away from an object, they will carry away a large amount of momentum. In the case of the sun's 4 billion year lifetime, the surface has lost a lot of momentum to photons, causing a slowdown of the uppermost 5 percent of the sun. This mechanism, called the Poynting-Robertson effect, has been observed in interplanetary dust, which feels the drag of the sun's radiation, causing it to fall from the asteroid belt into the inner solar system.

What affects dust inevitably affects the soup of super-heated gas in the sun's upper layers and, over its lifetime, the drag caused by photons being emitted from the sun has created a measurable and, until now, mysterious effect.

Using several years of data from NASA's Solar Dynamics Observatory (SDO), the researchers were able to measure waves traveling through the sun to precisely measure the size of the layer that is experiencing this slowdown. The technique, known as "helioseismology," is very similar to measuring the seismic waves travelling through the Earth to measure the strength of an earthquake. The material these seismic waves travel through changes the waves so seismologists can "see" underground.

Helioseismology: Probing the interior of a star PNAS

Though the sun isn't a solid planet made from rock and metal, its dense plasma interior also allows waves to travel, creating oscillations on the surface that can be measured. Helioseismology therefore allows astronomers to "see" into our nearest star, revealing many details about its interior that may not be obvious on the surface. And in this case, by using helioseismology and studying the sun's magnetic field passing from space into the sun's interior, we can gauge how much of a drag Einstein's special relativity has had on the sun's surface.

"This is a gentle torque that is slowing it down, but over the Sun's 5 billion year lifetime it has had a very noticeable influence on its outer 35,000 kilometers [22,000 miles]," said Kuhn. 

These findings have accepted for publication in the journal Physical Review Letters and can be previewed on the arXiv pre-print service.

Using our sun as a laboratory for other stars, Kuhn's team believe that a similar effect likely happens for all stars and could have a strong influence on stellar evolution. Now solar astronomers are very interested to understand how this solar slowdown impacts the sun's magnetic field that threads through the entire solar system. As the sun's magnetism is the root cause of space weather that can trigger solar flares and coronal mass ejections that could interfere with satellites and power grids, this research could have a key role to play in our understanding of solar impacts on Earth.

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• What form does the atomic nucleus? New discovery may explain the mysteries of the Universe.

• A new theory on the Creation of the Universe, disprove the Big Bang

Story source:
The above post is reprinted from materials provided by Space.com . Note: Materials may be edited for content and length.

Another '' Habitable Planet Proxima B'' this exoplanet has important water reserves

Significant water reserves were discovered exoplanet Proxima b, Swiss scientists say. Proxima b could be the closest planet outside the Solar System, a telluric exoplanet, which is in the habitable zone of the star Proxima Centauri.

Proxima b has the same specific features Earth, it can be considered akin to Earth and has significant reserves of water, having dimensions substantially similar to Earth.

Habitable Proxima-b Planet Found Next Door to Milky Way  photo: youtube

All this comes in support of the theory of a life on distant Proxima b exoplanet, say researchers at the University of Berne Swiss. They conducted measurements and necessary research and assume exoplanet Proxima b is slightly larger than Earth, then it reached conclusions that about 90% of the mass of the exoplanet is hard rock specific mountain area and 10% is water, specific oceans. Proxima b is a duplicate of Earth.

According to researchers who study planetary science, small planets are among the best candidates for the role of "second Earth", where life can exist. As a result, studies on such objects will be continued and expanded, according to researchers, reports RIA Novosti news agency.

Recently scientists announced that the star next to the star Proxima Centauri was also invented the closest exoplanet to Earth, which closely resembles the Sun, which was noted potentiometers training cycle dark points.

Remember that Proxima b exoplanet was discovered by researchers this year using spectral analysis method. Spectral analysis is a method of physical research composition of substances by examining its spectrum of radiation.

According to the study published, these variations indicate the presence of a planet, performing a complete orbit around the star in 11.2 days Proxima Centauri. Proxima b exoplanet it is almost 7.5 million kilometers or 0.05 AU of the star (about 5% of the distance from Earth to the Sun).



Other articles on the same theme:

• 4,000 confirmed exoplanets similar to Earth

• 10 fascinating planets outside the Solar System

• The new found alien world named HD 131399Ab

• Researchers have found another planet (Wolf 1061c) that can sustain life: Located just 14 light-years away

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