11.16.2016.近地太空发现诡异超速电子 能量来源疑团重重;地球磁场外侧的神秘电子加速现象:接近光速的高速运动,

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NASA’s MMS launches atop ULA Atlas V to study Earth’s magnetic …

NASA finds unusual origins of high-energy electrons
by Staff Writers
Greenbelt MD (SPX) Nov 16, 2016


This visualization represents one of the traditional proposed mechanisms for accelerating particles across a shock, called a shock drift acceleration. The electrons (yellow) and protons (blue) can be seen moving in the collision area where two hot plasma bubbles collide (red vertical line). The cyan arrows represent the magnetic field and the light green arrows, the electric field. Image courtesy NASA Goddard’s Scientific Visualization Studio/Tom Bridgman, data visualizer. Watch a video on the research here.

High above the surface, Earth’s magnetic field constantly deflects incoming supersonic particles from the sun. These particles are disturbed in regions just outside of Earth’s magnetic field – and some are reflected into a turbulent region called the foreshock. New observations from NASA’s THEMIS mission show that this turbulent region can accelerate electrons up to speeds approaching the speed of light. Such extremely fast particles have been observed in near-Earth space and many other places in the universe, but the mechanisms that accelerate them have not yet been concretely understood.

The new results provide the first steps towards an answer, while opening up more questions. The research finds electrons can be accelerated to extremely high speeds in a region farther from Earth than previously thought possible – leading to new inquiries about what causes the acceleration. These findings may change the accepted theories on how electrons can be accelerated not only in shocks near Earth, but also throughout the universe. Having a better understanding of how particles are energized will help scientists and engineers better equip spacecraft and astronauts to deal with these particles, which can cause equipment to malfunction and affect space travelers.

“This affects pretty much every field that deals with high-energy particles, from studies of cosmic rays to solar flares and coronal mass ejections, which have the potential to damage satellites and affect astronauts on expeditions to Mars," said Lynn Wilson, lead author of the paper on these results at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

The results, published in Physical Review Letters on Nov. 14, 2016, describe how such particles may get accelerated in specific regions just beyond Earth’s magnetic field. Typically, a particle streaming toward Earth first encounters a boundary region known as the bow shock, which forms a protective barrier between the sun and Earth. The magnetic field in the bow shock slows the particles, causing most to be deflected away from Earth, though some are reflected back towards the sun. These reflected particles form a region of electrons and ions called the foreshock region.

Some of those particles in the foreshock region are highly energetic, fast moving electrons and ions. Historically, scientists have thought one way these particles get to such high energies is by bouncing back and forth across the bow shock, gaining a little extra energy from each collision. However, the new observations suggest the particles can also gain energy through electromagnetic activity in the foreshock region itself.

The observations that led to this discovery were taken from one of the THEMIS – short for Time History of Events and Macroscale Interactions during Substorms – mission satellites. The five THEMIS satellites circled Earth to study how the planet’s magnetosphere captured and released solar wind energy, in order to understand what initiates the geomagnetic substorms that cause aurora. The THEMIS orbits took the spacecraft across the foreshock boundary regions. The primary THEMIS mission concluded successfully in 2010 and now two of the satellites collect data in orbit around the moon.

Operating between the sun and Earth, the spacecraft found electrons accelerated to extremely high energies. The accelerated observations lasted less than a minute, but were much higher than the average energy of particles in the region, and much higher than can be explained by collisions alone. Simultaneous observations from the Wind and STEREO spacecraft showed no solar radio bursts or interplanetary shocks, so the high-energy electrons did not originate from solar activity.

“This is a puzzling case because we’re seeing energetic electrons where we don’t think they should be, and no model fits them," said David Sibeck, co-author and THEMIS project scientist at NASA Goddard. “There is a gap in our knowledge, something basic is missing."

The electrons also could not have originated from the bow shock, as had been previously thought. If the electrons were accelerated in the bow shock, they would have a preferred movement direction and location – in line with the magnetic field and moving away from the bow shock in a small, specific region. However, the observed electrons were moving in all directions, not just along magnetic field lines. Additionally, the bow shock can only produce energies at roughly one tenth of the observed electrons’ energies. Instead, the cause of the electrons’ acceleration was found to be within the foreshock region itself.

“It seems to suggest that incredibly small scale things are doing this because the large scale stuff can’t explain it," Wilson said.

High-energy particles have been observed in the foreshock region for more than 50 years, but until now, no one had seen the high-energy electrons originate from within the foreshock region. This is partially due to the short timescale on which the electrons are accelerated, as previous observations had averaged over several minutes, which may have hidden any event. THEMIS gathers observations much more quickly, making it uniquely able to see the particles.

Next, the researchers intend to gather more observations from THEMIS to determine the specific mechanism behind the electrons’ acceleration.

信耶穌,信耶穌是耶和華成肉身,為拯救罪人代死在十字架上,第叄天復活、升天; 他是人類唯一之救主,天地之主宰,獨一之真神。信審判 信主耶穌必於世界末日,從天降臨,審判萬民;義人得永生,惡人受永刑
以賽亞書 24:13 在地上的萬民中,必像打過的橄欖樹,又像已摘的葡萄所剩無幾。賽19:1預示埃及之禍亂19 論埃及的默示。看哪,耶和華乘駕快雲,臨到埃及。信審判 信主耶穌必於世界末日,從天降臨,審判萬民;義人得永生,惡人受永刑。太8 這都是災難的起頭。24 看哪,耶和華使地空虛,變為荒涼;又翻轉大地,將居民分散。 6 地上的居民被火焚燒,剩下的人稀少

西番雅書 1Chinese Union Version Modern Punctuation (Traditional) (CUVMPT)

The Great Day of the Lord,

猶大亞們的兒子約西亞在位的時候,耶和華的話臨到希西家的玄孫、亞瑪利雅的曾孫、基大利的孫子、古示的兒子西番雅

耶和華說:「我必從地上除滅萬類。 我必除滅人和牲畜,與空中的鳥、海裡的魚,以及絆腳石和惡人。我必將人從地上剪除。」這是耶和華說的 「我必伸手攻擊猶大耶路撒冷的一切居民,也必從這地方剪除所剩下的巴力,並基瑪林的名和祭司, 與那些在房頂上敬拜天上萬象的,並那些敬拜耶和華指著他起誓,又指著瑪勒堪起誓的, 與那些轉去不跟從耶和華的,和不尋求耶和華也不訪問他的。」

你要在主耶和華面前靜默無聲,因為耶和華的日子快到。耶和華已經預備祭物,將他的客分別為聖。 「到了我耶和華獻祭的日子,必懲罰首領和王子,並一切穿外邦衣服的。 到那日,我必懲罰一切跳過門檻,將強暴和詭詐得來之物充滿主人房屋的。」 10 耶和華說:「當那日,從門必發出悲哀的聲音,從二城發出哀號的聲音,從山間發出大破裂的響聲。 11 瑪革提施的居民哪,你們要哀號!因為迦南的商民都滅亡了,凡搬運銀子的都被剪除。 12 那時,我必用燈巡查耶路撒冷,我必懲罰那些如酒在渣滓上澄清的,他們心裡說:『耶和華必不降福,也不降禍。』 13 他們的財寶必成為掠物,他們的房屋必變為荒場。他們必建造房屋卻不得住在其內,栽種葡萄園卻不得喝所出的酒。」

14 耶和華的大日臨近,臨近而且甚快。乃是耶和華日子的風聲,勇士必痛痛的哭號。 15 那日是憤怒的日子,是急難困苦的日子,是荒廢淒涼的日子,是黑暗、幽冥、密雲、烏黑的日子, 16 是吹角呐喊的日子,要攻擊堅固城和高大的城樓。17 「我必使災禍臨到人身上,使他們行走如同瞎眼的,因為得罪了我。他們的血必倒出如灰塵,他們的肉必拋棄如糞土。」 18 當耶和華發怒的日子,他們的金銀不能救他們。他的憤怒如火,必燒滅全地,毀滅這地的一切居民,而且大大毀滅

耶利米書 25:15-38Chinese Union Version Modern Punctuation (Traditional) (CUVMPT)

以怒杯喻列國之災

15 耶和華以色列的神對我如此說:「你從我手中接這杯憤怒的酒,使我所差遣你去的各國的民喝。 16 他們喝了就要東倒西歪,並要發狂,因我使刀劍臨到他們中間。」 17 我就從耶和華的手中接了這杯,給耶和華所差遣我去的各國的民喝, 18 就是耶路撒冷猶大的城邑並耶路撒冷的君王與首領,使這城邑荒涼,令人驚駭、嗤笑、咒詛,正如今日一樣。 19 又有埃及王法老和他的臣僕、首領以及他的眾民,20 並雜族的人民和烏斯地的諸王,與非利士地的諸王,亞實基倫加沙以革倫,以及亞實突剩下的人, 21 以東摩押亞捫人, 22 推羅的諸王,西頓的諸王,海島的諸王, 23 底但提瑪布斯和一切剃周圍頭髮的, 24 阿拉伯的諸王,住曠野雜族人民的諸王, 25 心利的諸王,以攔的諸王,瑪代的諸王, 26 北方遠近的諸王以及天下地上的萬國喝了,以後示沙克[a]王也要喝。

27 「你要對他們說:『萬軍之耶和華以色列的神如此說:你們要喝,且要喝醉,要嘔吐,且要跌倒不得再起來,都因我使刀劍臨到你們中間。』 28 他們若不肯從你手接這杯喝,你就要對他們說:『萬軍之耶和華如此說:你們一定要喝! 29 我既從稱為我名下的城起首施行災禍,你們能盡免刑罰嗎?你們必不能免,因為我要命刀劍臨到地上一切的居民。這是萬軍之耶和華說的。』

30 「所以你要向他們預言這一切的話,攻擊他們,說:『耶和華必從高天吼叫,從聖所發聲,向自己的羊群大聲吼叫。他要向地上一切的居民呐喊,像踹葡萄的一樣。 31 必有響聲達到地極,因為耶和華與列國相爭。凡有血氣的,他必審問;至於惡人,他必交給刀劍。這是耶和華說的。』」

牧者宜哀號哭泣

32 萬軍之耶和華如此說:「看哪,必有災禍從這國發到那國,並有大暴風從地極颳起。」 33 到那日,從地這邊直到地那邊,都有耶和華所殺戮的。必無人哀哭,不得收殮,不得葬埋,必在地上成為糞土。 34 牧人哪,你們當哀號、呼喊!群眾的頭目啊,你們要滾在灰中!因為你們被殺戮分散的日子足足來到,你們要跌碎,好像美器打碎一樣。 35 牧人無路逃跑,群眾的頭目也無法逃脫。 36 聽啊,有牧人呼喊,有群眾頭目哀號的聲音,因為耶和華使他們的草場變為荒場。 37 耶和華發出猛烈的怒氣,平安的羊圈就都寂靜無聲。 38 他離了隱密處像獅子一樣,他們的地因刀劍凶猛的欺壓,又因他猛烈的怒氣,都成為可驚駭的。

以賽亞書 19Chinese Union Version Modern Punctuation (Traditional) (CUVMPT)

預示埃及之禍亂

19 埃及的默示。

看哪,耶和華乘駕快雲,臨到埃及埃及的偶像在他面前戰兢,埃及人的心在裡面消化。 「我必激動埃及人攻擊埃及人,弟兄攻擊弟兄,鄰舍攻擊鄰舍,這城攻擊那城,這國攻擊那國。 埃及人的心神必在裡面耗盡,我必敗壞他們的謀略,他們必求問偶像和念咒的、交鬼的、行巫術的。 我必將埃及人交在殘忍主的手中,強暴王必轄制他們。」這是主萬軍之耶和華說的。

彼得後書 3:10Chinese Union Version Modern Punctuation (Traditional) (CUVMPT)

10 但主的日子要像賊來到一樣。那日,天必大有響聲廢去,有形質的都要被烈火銷化,地和其上的物都要燒盡了

我卻說:「我消滅了!我消滅了!我有禍了!詭詐的行詭詐,詭詐的大行詭詐。」17 地上的居民哪,恐懼、陷坑、網羅都臨近你。 18 躲避恐懼聲音的必墜入陷坑,從陷坑上來的必被網羅纏住,因為天上的窗戶都開了,地的根基也震動了。 19 地全然破壞,盡都崩裂,大大地震動了。 20 地要東倒西歪,好像醉酒的人;又搖來搖去,好像吊床。罪過在其上沉重,必然塌陷,不能復起

以賽亞書 24Chinese Union Version Modern Punctuation (Traditional) (CUVMPT)

居民背約主降災罰

24 看哪,耶和華使地空虛,變為荒涼;又翻轉大地,將居民分散。 那時百姓怎樣,祭司也怎樣;僕人怎樣,主人也怎樣;婢女怎樣,主母也怎樣;買物的怎樣,賣物的也怎樣;放債的怎樣,借債的也怎樣;取利的怎樣,出利的也怎樣。 地必全然空虛,盡都荒涼,因為這話是耶和華說的。 地上悲哀衰殘,世界敗落衰殘,地上居高位的人也敗落了。 地被其上的居民汙穢,因為他們犯了律法,廢了律例,背了永約。 所以地被咒詛吞滅,住在其上的顯為有罪;地上的居民被火焚燒,剩下的人稀少。 新酒悲哀,葡萄樹衰殘,心中歡樂的俱都嘆息。 擊鼓之樂止息,宴樂人的聲音完畢,彈琴之樂也止息了。 人必不得飲酒唱歌,喝濃酒的必以為苦。 10 荒涼的城拆毀了,各家關門閉戶,使人都不得進去。 11 在街上因酒有悲嘆的聲音,一切喜樂變為昏暗,地上的歡樂歸於無有。 12 城中只有荒涼,城門拆毀淨盡。 13 在地上的萬民中,必像打過的橄欖樹,又像已摘的葡萄所剩無幾

NASA – Q&A: Missions, Meetings, and the Radial Tire Model of the …

Oct 1, 2010 – … for the Magnetospheric MultiScale mission (or MMS), four spacecraft … as powerful as a billion atomic bombs and is responsible for magnetic …

http://www.spaceflightinsider.com/…/nasas-mms-launches-atop-a-ula-atlas-v-to-study-earths…

Mar 13, 2015 – NASA’s Magnetospheric Multiscale (MMS) satellites are ready to begin … even releasing energy roughly equivalent to billions of atomic bombs.

The biggest X-class flares are, by far, the largest explosions in the solar system and are awesome to watch. Loops tens of times the size of Earth leap up off the Sun’s surface when the Sun’s magnetic fields cross over each other and reconnect. In the biggest events, this reconnection process can produce as much energy as a billion hydrogen bombs.

When magnetic reconnection occurs in the sun it creates solar flares that explode off the surface. It can also cause coronal mass ejections, in which the solar flare belches up a storm of particles that hurtle outward into space — sometimes straight toward Earth. The planet’s own magnetic field protects people on the ground from these particle storms, but orbiting satellites are at risk of being damaged.

Magnetic reconnection also happens closer to Earth: the sun’s magnetic field lines stretch and wander all the way out past Mercury and Venus (where they are sometimes called interplanetary field lines), right to Earth’s doorstep. The field lines bump up against the Earth’s protective magnetic field — the magnetosphere — causing a few lines to break and reconnect.

Launch Tomorrow for Satellites Set to Solve Earth’s Magnetic Mysteries

The Magnetospheric Multiscale mission’s four satellites are designed to study the phenomenon responsible for powerful bursts of powerful magnetic particles

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March 12, 2015, 2:22 PM

NASA to study Earth and sun’s explosive interplay

The four satellites making up NASA’s $1.1 billion Magnetospheric Multiscale mission, or MMS, are stacked for launch Thursday in the nose of an Atlas 5 rocket. The satellites will work in concert to study the underlying physics of explosive interactions between the sun’s magnetic field and Earth’s.

 burn up 7

NASA is launching four satellites in a $1.1 billion mission to study the high-speed interactions between Earth’s magnetic field and the sun’s to learn more about the mechanisms responsible for the titanic energy discharges that drive auroras and play havoc with satellite navigation, communications and power grids.

The hard-to-study mechanism underlying space weather is known as magnetic reconnection, and it is the focus of NASA’s Magnetospheric Multiscale — MMS — mission scheduled for blastoff Thursday evening atop a United Launch Alliance Atlas 5 rocket.

Carrying the four MMS satellites stacked one atop the other in a protective nose cone fairing, the Atlas 5 was scheduled for takeoff from pad 41 at the Cape Canaveral Air Force Station at 10:44 p.m. EDT (GMT-4). Forecasters predicted a 70 percent chance of acceptable weather.

If all goes well, the satellites, built at NASA’s Goddard Space Flight Center in Greenbelt, Md., will be released at five-minute intervals starting about one hour and 32 minutes after liftoff.

Each 3,000-pound 12-foot-wide satellite features a suite of sensitive instruments and eight extendable antenna-like booms: four 197-foot-long radial wire booms and two 41-foot axial extensions for electric field sensors and two 16-foot booms carrying magnetometers.

When fully deployed, each satellite’s booms will sweep out an area the size of a baseball field as the spacecraft slowly rotate. All four satellites will be arranged in a pyramid formation, flying within about 6 miles of each other at their closest.

031215mmspad.jpg
A United Launch Alliance Atlas 5 rocket stands poised for liftoff at the Cape Canaveral Air Force Station to boost four NASA science satellites into orbit to study the underlying physics of explosive interactions between Earth’s magnetic field and the sun’s.
 NASA

The goal is to capture three-dimensional views of subtle magnetic interactions that occur very rapidly over very small regions of space.

The payoff will be a better understanding of how the sun’s magnetic field and solar winds interact with Earth’s magnetic field, how similar processes play out around black holes and across entire galaxies and possibly shed light on how magnetic fields can be used to help sustain nuclear fusion reactions for power generation on Earth.

The key is a phenomenon known as magnetic reconnection, the sudden annihilation of interacting magnetic fields that explosively heat and accelerate charged particles to extreme velocities.

“Magnetic fields exist throughout the universe and energy is often released by magnetic reconnection," said Jim Burch, MMS principal investigator at the Southwest Research Institute. “In the sun’s super-heated corona, magnetic fields create spectacular loops. The energy stored in these structures can release, creating explosive solar flares and coronal mass ejections.

“Intense fluxes of energetic particles and giant clouds of ionized gas and magnetic fields are ejected from the sun and travel throughout the solar system. When these clouds impact other magnetic fields such as the Earth’s, similar reconnection events occur and these cause intense magnetic activity and the auroral lights."

At the same time, he said, magnetic reconnection accelerates electrically charged particles “creating a hazard to space travelers and spacecraft, even disrupting ground-based power grids."

While scientists know magnetic reconnection occurs, they do not yet understand how or why. But they believe the answer will be found in the so-called “diffusion region" where events rapidly occur over very short scales.

Adjacent magnetic fields pointing in opposite directions tend to annihilate each other, releasing their magnetic energy and heating the charged particles in the surrounding environment," Burch said. “In this process, magnetic reconnection, the magnetic fields are torn apart and reattached to their neighbors.

“The mysterious part is what goes on inside the box labeled ‘diffusion region?’ With MMS, we’ll be able to probe the diffusion region for the first time with measurements down to the smallest scale of the plasma, the electron scale, to solve this mystery."

mmsorbit.jpg
An artist’s impression of NASA’s MMS satellites observing interactions between the magnetic fields of Earth and the sun.
 NASA

Paul Cassak, an associate professor at West Virginia University, described previous efforts to probe magnetic reconnection as similar to watching a football game for one minute and then waiting an hour before watching another minute.

“It would be really hard to figure out what’s going on in the football game," he said. “These are the problems that have been plaguing researchers studying magnetic reconnection, we can’t see the smaller scales and we can’t process the data fast enough to really understand what happens right at the place where magnetic reconnection happens. This makes it difficult to see, for example, how particles get accelerated and heated during magnetic reconnection events."

The MMS satellites represent a scientific assault on magnetic reconnection.

Each satellite, with its booms extended, covers a volume measuring 94 feet thick and 369 feet across. Each solar-powered spacecraft is equipped with 11 instruments made up of more than two-dozen sensors. Sensitive Global Positioning System navigation gear and thrusters will be used to maintain relative position and orientation.

The satellites will fly in two highly elliptical orbits that first will carry them through the magnetic reconnection zone on the Earth’s day side, where the solar wind, CMEs and flare debris crash into the protective bubble of Earth’s magnetic field.

The MMS spacecraft then will raise the high point of their orbit to study reconnection on the back side of the planet where Earth’s magnetic field tapers away in the solar wind.

That is where it’s particularly interesting, Burch said, “where you have reconnection in the tail of the magnetosphere. This is what produces the aurora and the currents that carry the energy of magnetic storms."

Burch said a better understanding of magnetic reconnection also could provide insights into long-standing problems that have prevented engineers from sustaining nuclear fusion reactions using magnetic containment.

“People for 20 years or more have been trying to harness nuclear fusion by trapping particles in a doughnut-shaped magnetic field and heating these up to something like 100 million degrees when fusion starts happening," Burch said. “If you could maintain that, we will have solved the energy crisis. Trouble is, it always crashes, these temperatures always come down (because of) magnetic reconnection."

“There are practical applications once you understand how magnetic reconnection works," he said.

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Is Earth’s protective shield cracking?

Bursts of deadly cosmic rays raises fears that our planet’s magnetic field is disappearing

  • Simulations indicate the Earth’s magnetic shield temporarily cracked
  • This was caused by magnetic reconnection of our magnetic field lines

  • This allowed lower energy galactic cosmic rays to enter our atmosphere
  • It could also be a sign our  magnetic shield is weakening, researchers said
  • This would cause widespread havoc on Earth including black outs and exposure to harmful UV radiation 

Read more: http://www.dailymail.co.uk/sciencetech/article-3901288/Is-Earth-s-protective-shield-cracking-Bursts-deadly-cosmic-rays-raises-fears-planet-s-magnetic-field-disappearing.html#ixzz4Q9ZMexyW
Follow us: @MailOnline on Twitter | DailyMail on Facebook

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Mysterious ‘megafast electrons’ are accelerated to the speed of light just outside Earth’s magnetic field – and scientists say strange discovery could change particle physics forever

  • Findings change the accepted theories on how electrons can be accelerated not only in shocks near Earth, throughout the universe
  • ‘Affects pretty much every field that deals with high-energy particles’ 

Read more: http://www.dailymail.co.uk/sciencetech/article-3936414/Mysterious-megafast-electrons-travelling-speed-light-just-outside-Earth-s-magnetic-field-change-particle-physics-forever.html#ixzz4Q9Yw7fpo
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NASA finds unusual origins of high-energy electrons

November 14, 2016 by Mara Johnson-Groh

NASA finds unusual origins of high-energy electrons
This image represents one of the traditional proposed mechanisms for accelerating particles across a shock, called a shock drift acceleration. The electrons (yellow) and protons (blue) can be seen moving in the collision area where two hot …more

High above the surface, Earth’s magnetic field constantly deflects incoming supersonic particles from the sun. These particles are disturbed in regions just outside of Earth’s magnetic field – and some are reflected into a turbulent region called the foreshock. New observations from NASA’s THEMIS mission show that this turbulent region can accelerate electrons up to speeds approaching the speed of light. Such extremely fast particles have been observed in near-Earth space and many other places in the universe, but the mechanisms that accelerate them have not yet been concretely understood.

The new results provide the first steps towards an answer, while opening up more questions. The research finds  can be accelerated to extremely high speeds in a  farther from Earth than previously thought possible – leading to new inquiries about what causes the acceleration. These findings may change the accepted theories on how electrons can be accelerated not only in shocks near Earth, but also throughout the universe. Having a better understanding of how  are energized will help scientists and engineers better equip spacecraft and astronauts to deal with these particles, which can cause equipment to malfunction and affect space travelers.

“This affects pretty much every field that deals with high-energy particles, from studies of cosmic rays to solar flares and coronal mass ejections, which have the potential to damage satellites and affect astronauts on expeditions to Mars," said Lynn Wilson, lead author of the paper on these results at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

The results, published in Physical Review Letters on Nov. 14, 2016, describe how such particles may get accelerated in specific regions just beyond Earth’s . Typically, a particle streaming toward Earth first encounters a boundary region known as the bow shock, which forms a protective barrier between the sun and Earth. The magnetic field in the bow shock slows the particles, causing most to be deflected away from Earth, though some are reflected back towards the sun. These reflected particles form a region of electrons and ions called the foreshock region.

Some of those particles in the foreshock region are highly energetic, fast moving electrons and ions. Historically, scientists have thought one way these particles get to such high energies is by bouncing back and forth across the bow shock, gaining a little extra energy from each collision. However, the new observations suggest the particles can also gain energy through electromagnetic activity in the foreshock region itself.

The observations that led to this discovery were taken from one of the THEMIS – short for Time History of Events and Macroscale Interactions during Substorms – mission satellites. The five THEMIS satellites circled Earth to study how the planet’s magnetosphere captured and released solar wind energy, in order to understand what initiates the geomagnetic substorms that cause aurora. The THEMIS orbits took the spacecraft across the foreshock boundary regions. The primary THEMIS mission concluded successfully in 2010 and now two of the satellites collect data in orbit around the moon.

This visualization represents one of the traditional proposed mechanisms for accelerating particles across a shock, called a shock drift acceleration. The electrons (yellow) and protons (blue) can be seen moving in the collision area where two hot …more

Operating between the sun and Earth, the spacecraft found electrons accelerated to extremely high energies. The accelerated observations lasted less than a minute, but were much higher than the average energy of particles in the region, and much higher than can be explained by collisions alone. Simultaneous observations from the Wind and STEREO spacecraft showed no solar radio bursts or interplanetary shocks, so the high-energy electrons did not originate from solar activity.

“This is a puzzling case because we’re seeing  where we don’t think they should be, and no model fits them," said David Sibeck, co-author and THEMIS project scientist at NASA Goddard. “There is a gap in our knowledge, something basic is missing."

The electrons also could not have originated from the bow shock, as had been previously thought. If the electrons were accelerated in the bow shock, they would have a preferred movement direction and location – in line with the magnetic field and moving away from the bow shock in a small, specific region. However, the observed electrons were moving in all directions, not just along magnetic field lines. Additionally, the  can only produce energies at roughly one tenth of the observed electrons’ energies. Instead, the cause of the electrons’ acceleration was found to be within the foreshock region itself.

“It seems to suggest that incredibly small scale things are doing this because the large scale stuff can’t explain it," Wilson said.

High-energy particles have been observed in the foreshock region for more than 50 years, but until now, no one had seen the high-energy electrons originate from within the foreshock region. This is partially due to the short timescale on which the electrons are accelerated, as previous observations had averaged over several minutes, which may have hidden any event. THEMIS gathers observations much more quickly, making it uniquely able to see the particles.

Next, the researchers intend to gather more observations from THEMIS to determine the specific mechanism behind the electrons’ acceleration.

 Explore further: THEMIS sees Auroras move to the rhythm of Earth’s magnetic field

Journal reference: Physical Review Letters search and more info website

Provided by: NASA’s Goddard Space Flight Center search and more info

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Blue Sky Science: What is a solar flare?

Oct 24, 2016,

Q: What is a solar flare?

— William Allen, 9, Lakeview Elementary School, Robbinsdale, Minn.

A: A solar flare is a release of magnetic energy from the sun. The energy is stored as a magnetic field around the sun, and then is released with energetic particles and waves coming from the solar surface.

Huge amounts of energy are released during solar flares, which can be spectacular events.

These solar flare events are related to a process called magnetic reconnection, or the annihilation of the magnetic field.

There are magnetic fields that are of opposite polarity, with some magnetic fields going one direction and other magnetic fields going the opposite way.

When these opposing magnetic fields come into contact, reconnection occurs and may be explosive, as in the case of solar flares.

Scientists still debate the cause of the explosions. In general, the sun is undergoing an 11-year cycle called the solar cycle that affects the sun’s radiation, number of solar flares and number of sun spots.

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This cycle reflects fluctuations in solar activity and changes the polarity of the sun every 11 years.

Solar flares can affect life on Earth in a number of ways. They are responsible for beautiful natural phenomena like the auroras.

Scientists today are most concerned about effects on sensitive radioelectronic equipment up in orbit. Solar flares can damage this equipment in orbit, affect communications systems on airplanes, or even short-circuit electronic systems on the ground.

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High-speed electrons have been spotted outside Earth’s magnetic field, and NASA can’t explain it 

So fast, they break current physics models.

 
BEC CREW 

16 NOV 2016

In the region of space just outside Earth’s magnetic field, NASA has detected electrons that are being accelerated to almost the speed of light – and no one can explain why.

In fact, our current understanding of particle physics says this kind of acceleration should be impossible so far out from the magnetosphere, and now physicists are trying to figure out what kind of force can be pushing them to such speeds.

“This is a puzzling case because we’re seeing energetic electrons where we don’t think they should be, and no model fits them," says one of the researchers, David Sibeck from NASA’s Goddard Space Flight Centre. “There is a gap in our knowledge, something basic is missing."

The high-speed electrons were detected by NASA’s THEMIS mission, which sent five satellites into Earth’s orbit to observe how our planet’s protective magnetic field captures and releases solar winds and cosmic radiation.

Their primary goal was to help scientists understand what triggers geomagnetic storms that can wreak havoc on communications systems on Earth, but once they hit the foreshock boundary region just outside of Earth’s magnetic field, they opened up a whole new set of questions.

High-energy electrons are constantly being hurled at us from the Sun, but are deflected by our super-strong magnetic field before they can pose any kind of threat.

When this interaction occurs, the electrons encounter the outermost layer of the magnetosphere called the bow shock, and its magnetic field slows them down, causing most of them to be deflected back into space.

But some of them will be reflected back towards the Sun, forming a band of high-energy, super-fast electrons just outside the magnetosphere called the foreshock boundary region.

For decades, it was assumed that these electrons got their energy and speed from being bounced back and forth across the bow shock.

Physicists thought that every time these particles collided with our magnetic shield, they got more and more energy, and could be accelerated to almost the speed of light.

But new observations from the THEMIS satellites have revealed that the electrons can also gain energy through electromagnetic activity in the foreshock region itself – and no one can explain how.

In fact, it looks like these electrons never even made it to the bow shock.

“The electrons … could not have originated from the bow shock, as had been previously thought," says NASA.

“If the electrons were accelerated in the bow shock, they would have a preferred movement direction and location – in line with the magnetic field and moving away from the bow shock in a small, specific region."

Instead, the team found that the electrons were moving in all directions – not just along magnetic field lines – and the bow shock could only account for roughly one-tenth of the electrons’ energies.

The researchers have concluded that the cause of the electrons’ acceleration must be from within the foreshock boundary region itself.

“These findings may change the accepted theories on how electrons can be accelerated not only in shocks near Earth, but also throughout the Universe," says NASA.

The team plans on gathering more data from the THEMIS satellites to figure out how exactly these electrons are being accelerated to such incredible speeds, but one of the researchers, Lynn Wilson, suggests that we need to start thinking in much smaller scales in order to find the answers.

“It seems to suggest that incredibly small scale things are doing this, because the large scale stuff can’t explain it," she said.

The results have been published in Physical Review Letters.

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NASA discovers mysterious super-fast electrons whizzing above Earth

Understanding the source could aid space missions

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Electrons are being whipped to speeds close to the speed of light just outside the Earth’s magnetic field, and scientists aren’t sure why.

NASA’s Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission has discovered these extremely fast particles farther from Earth than previously thought possible.

The Sun flings supersonic electrons out to space, and some fly towards Earth but are deflected away by Earth’s magnetic field.

The series of the magnetic fields covers the Earth and creates a protective bubble known as the magnetosphere. As the magnetosphere moves through space, a bow shock ripples through space as the electrons are slowed and deflected away.

Some electrons end up being reflected towards the Sun, and end up in a pool surrounding the bow shock in the foreshock region.

A paper published in Physical Review Letters [paywalled] shows that some electrons in the foreshock are being excited to relativistic speeds.

Photo credit: NASA/SGFC

Scientists have always believed that electrons reach such fast speeds because they are bounced back and forth across the bow shock, gaining speed with each collision.

But, after analyzing data taken from NASA’s THEMIS spacecraft, a team of scientists led by NASA’s Goddard Space Flight Center have found that the average energy of the electrons does not match the energies given from the collisions alone.

Observations made by NASA’s Heliophysics, Wind, and STEREO spacecrafts revealed no solar radio bursts or interplanetary shocks that could have imparted extra energy to the electrons. The high speeds cannot be explained with any solar activity and do not originate from the bow shock area, leaving scientists perplexed.

“This is a puzzling case because we’re seeing energetic electrons where we don’t think they should be, and no model fits them,” said David Sibeck, coauthor of the paper and a project scientist working on the THEMIS mission. “There is a gap in our knowledge – something basic is missing.”

Although high-energy electrons have been observed in the foreshock region for more than 50 years, it wasn’t known that they sprang from the foreshock region itself. It could be because the electrons are accelerated over a short burst of time, and most spacecrafts can only detect changes over minutes.

Solving the mechanism that produces these relativistic electrons is important, said Lynn Wilson, lead author of the paper and researcher at NASA’s Goddard Space Flight Center.

“This affects pretty much every field that deals with high-energy particles, from studies of cosmic rays to solar flares and coronal mass ejections, which have the potential to damage satellites and affect astronauts on expeditions to Mars.”

Relativistic electrons can cause equipment to fail and even penetrate through space suits, giving astronauts a strong dose of radiation capable of damaging DNA. ®

Sponsored: Customer Identity and Access Management

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地球磁场外侧的神秘电子加速现象:接近光速的高速运动

2016年11月16日 10:25 新浪科技 微博

这张图像表示的是一种传统的空间粒子加速理论模型,即所谓“激波漂移加速”。黄色的是电子,蓝色是质子,可以看到这两种带电粒子在一个碰撞区域内运动,在此区域内有两个高温等离子气泡(红色垂直线)相互碰撞。青色尖头代表磁场,而浅绿色箭头代表的是电场

示意图:正在地球附近空间工作的THEMIS卫星星座。整个THEMIS星座一共有5颗卫星围绕地球飞行,目的是观察地球磁场如何捕获及释放太阳风粒子能量,从而理解导致极光出现的地磁亚暴现象是如何发生的  示意图:正在地球附近空间工作的THEMIS卫星星座。整个THEMIS星座一共有5颗卫星围绕地球飞行,目的是观察地球磁场如何捕获及释放太阳风粒子能量,从而理解导致极光出现的地磁亚暴现象是如何发生的

  新浪科技讯 北京时间11月16日消息,据国外媒体报道,我们之所以能够安然存活于地球之上,一部分原因是地球磁场正时刻阻挡着来自太阳的大量高能粒子流,使其不能大量抵达地面并对我们产生伤害。这些带电粒子在地球磁场的阻挡下发生偏移,一部分会进入一个被称作“激波前兆区”(foreshock)的区域。近日,美国宇航局THEMIS探测器获得的数据显示这一狂暴区域能够将电子加速到接近光速的高速运动状态。在此之前,科学家们已经在接近地球的空间内发现过这类速度极高的粒子,更多这样的粒子存在于宇宙空间之中,但它们背后的加速机制却一直未能得到明确解释。

  而这项最新研究得到的结果朝着给出这一问题的答案迈出了第一步,但同时也引出的新的问题。研究人员发现电子被加速到极高速度的区域远远超出了此前理论认为可能的最远边界,从而引出的关于这些电子被加速背后机制的新问题。这项研究成果将有望改写现有关于电子如何在地球周围的激波区,以及宇宙各处被加速的理论认识。而对于粒子加速方面的更深刻认识则将帮助科学家和工程师们在未来的飞船设计中为宇航员和设备提供更好的辐射防护设施,从而确保宇宙航行过程中的安全无虞。

  这项研究的第一作者,美国宇航局位于马里兰州格林贝特戈达德空间飞行中心的林恩·威尔森(Lynn Wilson)表示:“这将对几乎所有与高能粒子相关的领域产生影响,从宇宙射线研究到太阳耀斑和日冕物质抛射。这些事件都将有可能对人造卫星以及飞往火星的宇航员们的安全构成威胁。”

  相关研究结果已经在11月14日出版的《物理评论快报》上发表。在这篇论文中,科学家们描述了这些粒子是如何在地球磁场外侧的某些特定区域被加速的。在典型情况下,一个飞向地球的粒子首先会遇到一个被称作“弓形激波区”(bow shock)的区域,该区域在地球与太阳之间构建起一个防护屏障。在弓形激波区内的磁场让粒子减速,从而让绝大部分飞向地球的粒子改变方向,偏离地球,其中还会有一部分被反弹回来,重新朝太阳方向飞行。这些被反弹回去的粒子会聚集在一起,形成一个充满电子和离子的区域,被称作“激波前兆区”。

  在该区域的一部分粒子是能量非常高,运动速度很快的电子和离子。在历史上,科学家们曾经设想过这些粒子在弓形激波区内部来回反弹,并在每一次反弹中获得能量,从而实现加速的理论。而此次的研究却发现这些粒子在激波前兆区本身的电磁活动中也能获得能量。

  导出这项发现的相关数据是由美国宇航局的其中一个THEMIS探测器获得的,这是“亚暴期事件与大尺度相互作用时间历史”探测器的缩写。整个THEMIS星座一共有5颗卫星围绕地球飞行,目的是观察地球磁场如何捕获及释放太阳风粒子能量,从而理解导致极光出现的地磁亚暴现象是如何发生的。THEMIS探测器在其飞行过程中会穿越激波前兆区边界。THEMIS主要任务期已经于2010年顺利结束,现在该项目仍有两颗探测器正在月球轨道上运行并采集数据。

  在地球与太阳之间飞行探测期间,THEMIS飞船发现在某些区域电子会被加速到极高的能级。这样的加速持续时间不超过1分钟,但是其能级明显要比该区域内其他粒子要高得多,并且也远远超过了用碰撞理论能够解释的范围。来自Wind 以及 STEREO卫星提供的同步观测数据显示在此期间并未发生太阳射电暴发或者行星际激波现象,因此这些高能电子并非是由太阳活动产生的。

  大卫·斯贝克(David Sibeck)是这项研究的合作者,也是美国戈达德空间飞行中心的THEMIS项目科学家。他说:“这令人困惑,因为我们在不该存在高能电子的区域见到了它们,并且没有任何现有理论模型能够对此给出解释。这是我们知识中的空挡,某些基础理论出现了缺失。”

  这些高能电子也不可能如此前一直以为的那样来自弓形激波区。如果这些电子是在弓形激波区被加速的,它们应当会沿着某个特定的方向和位置——具体的说应当是与地球磁场的磁感线方向一致的。然而观测到的电子加速却是沿着各个不同方向的,而并不仅仅是沿着地球磁感线。另外,弓形激波能够赋予电子的能量也只是观测到实际情况的十分之一左右。最终,科学家们认为这些电子获得能量从而实现加速背后的谜底还是隐藏在激波前兆区内部。

  威尔森表示:“看起来这就是一种极小尺度上的机制产生了影响,因为宏观尺度上的机制无法对此进行解释。”

  早在50多年前,科学家们便已经在激波前兆区内观测到高能粒子,但直到今天,还无人观测到在激波前兆区内产生出来的高能电子。究其原因,首先是电子在这里得到加速的时间实在太过于短暂,此前的观测数据间隔都达到数分钟,在此期间很有可能会忽略很多事件。而THEMIS探测项目采集数据的时间分辨率要高得多,从而能够观测到这些粒子的存在。

接下来,研究人员们计划利用THEMIS探测器采集更多数据,以便最终确认电子神秘加速事件背后的真正机制。(晨风)

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近地太空发现诡异超速电子 能量来源疑团重重

2016-11-16 10:20:37 来源:  网易科技报道

网易科技讯11月16日消息,据英国《每日邮报》报道,NASA在地球磁场附近的太空中发现了被加速到近光速的电子,在名为“前震(foreshock)”的动荡区域中,这些粒子以神秘的方式获得了高能量,这些能量是弓形激波引发的能量的十倍。但是这种现象的原因让NASA都觉得困惑,这一诡异的新发现有望永远改变粒子物理学领域的某些理论。

近地太空发现诡异超速电子 能量来源疑团重重

NASA表示,这一发现让他们迈出了寻求答案的第一步,但同时却引发了更多的疑问。

在地球磁场以外的不远区域中,粒子受到了干扰,其中一些被反射到名为前震的动荡区域中,在那里它们以某种方式被加速到超快的速度

NASA戈达德太空飞行中心把这些发现撰写成文章并发表在《物理评论快报(Physical Review Letter)》中,首席撰稿人林恩?威尔逊(Lynn Wilson)表示,“这几乎影响了与高能粒子相关的每一个领域,例如,对宇宙射线、太阳耀斑和日冕物质抛射的研究。这些粒子有可能破坏卫星,对宇航员的火星探险带来不利影响。”

近地太空发现诡异超速电子 能量来源疑团重重

地面上方的地球磁场不断使来自太阳的超音速粒子改变方向并发生偏移。

NASA的新发现表明,这一动荡区域会让电子加速至接近光速。

先前科学家们在近地太空和宇宙中的许多其他地方发现过这些高速粒子,但并不理解它们的加速原理。

现在这些新发现可能会改变此前一些得到公认的理论。这些理论认为,电子不仅仅在近地太空的震荡区域中会得到加速,在整个宇宙中都是如此。

更好地了解粒子如何获得能量将有助于科学家和工程师为航天器和宇航员提供能够应对这些粒子的设备,这些粒子可能导致设备出现故障。

NASA的这篇文章描述了这些颗粒如何在地球磁场以外及附近的特定区域得到加速。

近地太空发现诡异超速电子 能量来源疑团重重

通常情况下,朝着地球流动的颗粒首先遭遇名为弓形激波(bow shock)的边界区域,该区域在太阳风和地球之间形成一道保护屏障。太阳风是指来自太阳的持续和不断变化的带电粒子流。

弓形激波中的磁场不仅让颗粒减速,还会让大多数颗粒偏离地球,有一些颗粒因反射而朝向太阳方向折回。

这些被反射的电子和离子形成了前震区域。

前震区域中的一些颗粒是具有高能量的、快速移动的电子和离子。

在过去,科学家们认为这些粒子获得这种高能量的一种方式是通过弓形激波来回弹跳,并从每次碰撞中获得些许额外的能量。

不过,新发现表明,这些颗粒也可通过前震区域本身的电磁活动获得能量。

THEMIS项目的科学家兼合作撰稿人大卫-斯贝克(David Sibeck)表示,“这种情况令人困惑,因为我们原以为,这些高能量电子不会出现在这些地方,目前也没有已知的模式符合它们的特征。我们对太空的认知存在缺口,一些基本知识的缺失。”

研究者表示,按照过往的认识,这些电子不可能源自弓形激波。

如果电子是在弓形激波中被加速,它们将出现与磁场一致的运动方向和位置,并在一些小范围的特定区域内逐渐远离弓形激波。

然而,NASA研究者此次观察到的电子是沿着所有方向移动,而不仅仅沿着磁场线移动。

此外,弓形激波产生的能量大约仅是此次发现的电子能量的十分之一。

电子加速的原因究竟是什么?解决这一奥妙的关键在于前震区域。

威尔逊说,“这似乎表明,这令人难以置信的微观现象难以通过宏观原理来解释。”

接下来,研究者打算通过THEMIS项目收集更多的观察结果,以确定电子加速背后的具体机制。(悠云)

王真 本文来源:网易科技报道
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