Plasma Shied Protecting the Earth
~ 地球を守るプラズマ・シールド ~

スクリーンショット 2016-05-22 20.30.39

This image shows a color-coded geographic representation of ultra-relativistic electron fluxes, based on orbital tracks of the Van Allen Probe B spacecraft projected onto the geographical equatorial plane. As the spacecraft precesses in its elliptical orbit around the Earth, it forms a “spirograph” pattern in the Earth-centered coordinate system. Inside of this radial distance is an almost complete absence of electrons, forming the “slot” region. The superimposed circle shows a sharp, distinctive inner boundary for ultra-relativistic electrons, and how generally symmetric this boundary is around Earth.



Plasma shield

Researchers find that Earth’s “plasmaspheric hiss” protects against a harmful radiation belt.

Jennifer Chu | MIT News Office
November 26, 2014

High above Earth’s atmosphere, electrons whiz past at close to the speed of light. Such ultrarelativistic electrons, which make up the outer band of the Van Allen radiation belt, can streak around the planet in a mere five minutes, bombarding anything in their path. Exposure to such high-energy radiation can wreak havoc on satellite electronics, and pose serious health risks to astronauts.


Now researchers at MIT, the University of Colorado, and elsewhere have found there’s a hard limit to how close ultrarelativistic electrons can get to the Earth. The team found that no matter where these electrons are circling around the planet’s equator, they can get no further than about 11,000 kilometers from the Earth’s surface ― despite their intense energy.


What’s keeping this high-energy radiation at bay seems to be neither the Earth’s magnetic field nor long-range radio waves, but rather a phenomenon termed “plasmaspheric hiss” ― very low-frequency electromagnetic waves in the Earth’s upper atmosphere that, when played through a speaker, resemble static, or white noise.


Based on their data and calculations, the researchers believe that plasmaspheric hiss essentially deflects incoming electrons, causing them to collide with neutral gas atoms in the Earth’s upper atmosphere, and ultimately disappear. This natural, impenetrable barrier appears to be extremely rigid, keeping high-energy electrons from coming no closer than about 2.8 Earth radii ― or 11,000 kilometers from the Earth’s surface.


“It’s a very unusual, extraordinary, and pronounced phenomenon,” says John Foster, associate director of MIT’s Haystack Observatory. “What this tells us is if you parked a satellite or an orbiting space station with humans just inside this impenetrable barrier, you would expect them to have much longer lifetimes. That’s a good thing to know.”


Foster and his colleagues, including lead author Daniel Baker of the University of Colorado, have published their results this week in the journal Nature.

Shields up

The team’s results are based on data collected by NASA’s Van Allen Probes ― twin crafts that are orbiting within the harsh environments of the Van Allen radiation belts. Each probe is designed to withstand constant radiation bombardment in order to measure the behavior of high-energy electrons in space.


The researchers analyzed the first 20 months of data returned by the probes, and observed an “exceedingly sharp” barrier against ultrarelativistic electrons. This barrier held steady even against a solar wind shock, which drove electrons toward the Earth in a “step-like fashion” in October 2013. Even under such stellar pressure, the barrier kept electrons from penetrating further than 11,000 kilometers above Earth’s surface.


To determine the phenomenon behind the barrier, the researchers considered a few possibilities, including effects from the Earth’s magnetic field and transmissions from ground-based radios.


For the former, the team focused in particular on the South Atlantic Anomaly ― a feature of the Earth’s magnetic field, just over South America, where the magnetic field strength is about 30 percent weaker than in any other region. If incoming electrons were affected by the Earth’s magnetic field, Foster reasoned, the South Atlantic Anomaly would act like a “hole in the path of their motion,” allowing them to fall deeper into the Earth’s atmosphere. Judging from the Van Allen probes’ data, however, the electrons kept their distance of 11,000 kilometers, even beyond the effects of the South Atlantic Anomaly ― proof that the Earth’s magnetic field had little effect on the barrier.


Foster also considered the effect of long-range, very-low-frequency (VLF) radio transmissions, which others have proposed may cause significant loss of relatively high-energy electrons. Although VLF transmissions can leak into the upper atmosphere, the researchers found that such radio waves would only affect electrons with moderate energy levels, with little or no effect on ultrarelativistic electrons.


Instead, the group found that the natural barrier may be due to a balance between the electrons’ slow, earthward motion, and plasmaspheric hiss. This conclusion was based on the Van Allen probes’ measurement of electrons’ pitch angle ― the degree to which an electron’s motion is parallel or perpendicular to the Earth’s magnetic field. The researchers found that plasmaspheric hiss acts slowly to rotate electrons’ paths, causing them to fall, parallel to a magnetic field line, into Earth’s upper atmosphere, where they are likely to collide with neutral atoms and disappear.


Mary Hudson, a professor of physics at Dartmouth College, says the data from the Van Allen probes “are providing remarkably detailed measurements” of the Earth’s radiation belts and their boundaries.

“These new observations confirm, over the two years since launch of the Van Allen probes, the persistence of this inner boundary, which places additional constraints on theories of particle acceleration and loss in magnetized astrophysical systems,” says Hudson, who did not participate in the research.


Seen through “new eyes”

Foster says this is the first time researchers have been able to characterize the Earth’s radiation belt, and the forces that keep it in check, in such detail. In the past, NASA and the U.S. military have launched particle detectors on satellites to measure the effects of the radiation belt: NASA was interested in designing better protection against such damaging radiation; the military, Foster says, had other motivations.



“In the 1960s, the military created artificial radiation belts around the Earth by the detonation of nuclear warheads in space,” Foster says. “They monitored the radiation belt changes, which were enormous. And it was realized that, in any kind of nuclear war situation, this could be one thing that could be done to neutralize anyone’s spy satellites.”


The data collected from such efforts was not nearly as precise as what is measured today by the Van Allen probes, mainly because previous satellites were not designed to fly in such harsh conditions. In contrast, the resilient Van Allen Probes have gathered the most detailed data yet on the behavior and limits of the Earth’s radiation belt.


“It’s like looking at the phenomenon with new eyes, with a new set of instrumentation, which give us the detail to say, ‘Yes, there is this hard, fast boundary,’” Foster says.


This research was funded in part by NASA.





Israel-Palestine: Social Media As a Tool Of Oppression

04/18/2016 06:01 pm ET

去年の暮れ頃、イスラエル警察は15歳のタマラ・アブ・ラバン(Tamara Abu Laban)という女性の家を荒らし彼女を逮捕・勾留しました。タマラの犯罪は一体なんだったのでしょうか?タマラのフェースブックのステータスをアラビア語で「許して」と更新したことですか?
























●イスラエルの現実に失望したユダヤ人による反シオニズム運動 2






シオニストの政治的策動は、一時的には成功するかもしれないが、長い目で見れば、その命運は尽きているのである。 〈中略〉






ネトゥレイ・カルタの支持者はラビ文学に重きを置く。その中では、ユダヤ人はまずその罪のためにイスラエルの地を逐われる、と書かれている。それに加え、如何なるかたちでの強制力によるイスラエル再建も神の意志に反する(バビロニアタルムード、tractate Ketuboth 111)、という少数派の観点を持つ。




超正統派 (ユダヤ教)


Googleで「Neturei Karta statement」で検索









Israel-Palestine: Social Media As a Tool Of Oppression

04/18/2016 06:01 pm ET

Late last year, Israeli police arrested and detained 15-year-old Tamara Abu Laban after storming her house. Tamara’s crime? Updating her Facebook status with the words “forgive me” in Arabic.

In most places in the world, a cryptic, if not slightly dramatic post written by a teenage girl seeking “likes” from her friends would hardly be cause for reaction. But if you are a Palestinian growing up in Occupied East Jerusalem like Tamara, even a vague and “angsty” personal Facebook status may become grounds for arrest.

Israeli authorities interpreted the post as expressing intent to carry out a violent act of resistance. The teenager was released under the condition that she would post bail of 1,500 Israeli shekels, remain under house arrest for 5 days, and pay another 10,000.

Tamara’s story is one of many, and those numbers are rising both for adults and minors. According to a new report, by Hamleh – The Arab Center for the Advancement of Social Media, 2015 saw a surge in the number of Palestinians being arrested on the charge of “incitement through social media.” The Hamleh report analyzed Palestinian internet and social media usage in 2015, and found that since last October – the start of the latest Palestinian uprising – the number of arrests Israel has made based on social media activity has more than doubled.

The Palestinian Prisoners Club, a non-governmental organization dealing with prisoners’ rights, estimates that more than 150 arrests took place between October and February 2016 based on Facebook posts expressing opinions on the uprising.

Another prominent case is that of the poet Dareen Tatour, who was first arrested on October 10 — without a search order or arrest warrant — for posting images of “martyrs” on her Facebook page and videos of protests with her voice in the background reading her poetry. It is important to note that the word “martyr” is used to describe any Palestinian who dies from any cause related to the conflict.

In November, Tatour was charged with “incitement of violence, and supporting terrorist groups through Facebook,” among other allegations. The only evidence was her Facebook posts and lines from her poetry. Tatour, who holds Israeli citizenship, remains under house arrest to this day, forced to wear an electronic handcuff, and has been banned from using the internet. Other Palestinians arrested include administrative detainees who are held for months at a time without trial, evidence, or access to legal counsel.

There is no formal legislation that covers legal action with regard to the accusation of incitement through social media. The lack of a legal framework has led to an arbitrary handling of case-by-case individuals, often depending on the broader political climate as in the October uprising. According to Addameer, a Palestinian human rights NGO that works to support political prisoners, some detainees have even been charged based on the number of shares, likes and the prominence of their Facebook posts, which seems to concern Israeli authorities more than the actual content of the posts.

The very definition of “incitement” is thus being stretched when it comes to evaluating the significance of social media in the everyday lives of Palestinians, especially activist voices, engaging in political conversations or expressing grievances against the Israeli occupation.

Israeli officials have made efforts to tighten security measures surrounding social media activity. The Israeli Deputy Foreign Minister and Member of Knesset Tzipi Hotovely, met with representatives of YouTube and Google in November to discuss methods of censoring videos and shutting down online accounts created by Palestinians, which she described as “inciting violence and terrorism.” Google later denied claims that it had reached an agreement to collaborate with Israel on a special monitoring mechanism for online materials published by Palestinians, and instead said that its current Community Guidelines would suffice in protecting against online incitement.

Israel alleges that the sharing of online videos played a critical role in the rise of violence in the final months of 2015. However, journalists and human rights organizations have spoken out against policies of censorship that violate freedom of speech. In fact, all foreign journalists who report in the Occupied Palestinian Territory are already “required to register with the Israeli military, and any footage that they film is required to go through the Israeli Military Censor’s office before it can be released.”

On the other hand, Palestinians’ digital rights and access to the internet are compromised in very basic ways, because Israel controls the infrastructure and services of Palestinian telecommunication companies in the West Bank. The Israeli government recently announced that it would finally allow Palestinians in the West Bank to access 3G wireless networks, making this area one of the last in the world to have access to 3G technologies after years of restrictions. Though it is unclear what motivated this change in policy, many have assumed it was an appeasement tactic as a response to the popular uprising.

Nevertheless, Palestinian social media use is growing in significance in terms of influencing political events, public perceptions and developments on the ground. Hamleh notes that Palestinian participation on social media is largely characterized by political themes, with the most popular posts being related to political campaigns and issues.

In 2015 online activists saw their hashtags, photos and videos being shared worldwide and often getting picked up by mainstream foreign media. For example, one of the hashtags trending on Palestinian social media in the months before the October uprising was #it_will_not_be_divided, which aimed to bring attention to Israeli policies preventing Palestinian men and women from entering al-Aqsa Mosque during August and September.

In addition, online media is increasingly a central source of information for activists and organizers. For example, the political prisoner Mohammad Alan’s hunger strike against detention without charge and his subsequent hospitalization led to a widely followed social media campaign with the hashtag #Mohammed_Alan, mobilizing activists and others to protest outside the hospital.

The most important role of social media seems to be that it is opening new opportunities for Palestinians who are separated by the many physical borders Israel has erected to freedom of movement, including the Separation Wall and checkpoints, to connect and build solidarity movements with one another.

Social media is giving Palestinian activists new tools to organize nonviolent protests and advocate for their rights. Of course, the effectiveness of their advocacy necessitates clashing with the Israeli occupation forces in order to realize and acquire their right to freedom of expression, privacy, and access to the internet with quality service.

Palestinians, Israelis and the international community should pressure the Israeli government to honor their proclaimed democratic values and stop arbitrary arrests. Silencing and intimidating teenagers and poets for using social media are not characteristics of a democracy.