Space Puzzle: What’s Behind Earth’s Mysterious New Radiation Belt?

The Van Allen Belts, known to science for more than half a century, throw astronomers a sudden curve

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NASA

Not all that far above your head is a particle accelerator that would put the Large Hadron Collider to shame. There, charged particles, some carried in by the solar wind, some created by cosmic rays, whiz along in a complicated dance, trapped by Earth‘s magnetic field in a pair of enormous concentric rings nestled around our planet, stretching from a low of about 1,000 miles (1,600 km) above the ground to a high of 20,000 mi. (32,000 km). These cosmic donuts, known as the Van Allen radiation belts, were one of the very first discoveries of the Space Age, detected when the Geiger counters placed on NASA‘s early Explorer satellites by James Van Allen and colleagues recorded high levels of radiation.

That was in 1958. Since then, scientists who study space weather—the complex interplay of the Earth’s magnetic field and the energy and particles sloughed off by the Sun—have worked to understand how these belts form and how to predict the outer belt’s sometimes wild behavior, which can include enormous expansion or contraction over the course of a few days. Now, however, the twin Van Allen Probes, which were launched last summer and represent NASA’s latest and best-equipped mission into the radiation belts, have revealed something remarkable that has theorists shaking their heads: Mere days after the probes switched on early last September, according to a report this week’s Science, a third radiation belt appear, nestled in between the other two at about 8,000 mi. (12,700 km) up.

At first, Daniel Baker, director of the Laboratory for Atmospheric and Space Physics at the University of Colorado and the lead author of the paper, thought there must be some mistake. “It looks so odd, so unexpected, that I start to get a sinking feeling that maybe something’s wrong with our instruments,” he recalls. But everything was in working order, with both probes sending back identical observations. The slender third belt remained for about a month before being destroyed by a coronal mass ejection—an eruption of energy and particles from the sun that sent a shock wave racing towards Earth.

(FROM THE TIME ARCHIVES: James Van Allen cover; May 4, 1959)

The formation of a third belt was more than just a scientific puzzle—it presents a real-world problem. Knowing where the radiation belts lie and how the Sun’s periodic spurts of activity affect them is important for keeping satellites that provide telecommunication and GPS services intact. High-energy particles in the belts can cause disastrous shorts in electronics and occasionally turn a multi-million dollar device into junk.

“We need to understand the variations in the radiation belts to help design satellites better,and forecast periods of high risk,” Richard Horne, a physicist at the British Antarctic Survey who studies space weather and was not involved in the report, wrote in an email. “While most commercial satellites orbit at geostationary orbit [an altitude of about about 22,000 mi., or 35,000 km], which is in the outer region of the radiation belts, the new growth area is medium Earth orbit, for the positioning and navigational satellites, and also for new types of commercial satellites.”

The third belt may not necessarily be a freak occurrence, either. Previous satellites haven’t been properly equipped to observe the area in which the belt is visible, says Shrikanth Kanekal, a researcher at NASA’s Goddard Space Flight Center and an author of the paper. “But after we saw the third belt, we went back and we found hints of these third-belt-type structures in different satellites.” It’s just the sort of revelation that the Van Allen Probes, with their top-of-the-line instrumentation, were intended to provide—even if this particular one was not at all anticipated.

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The next step will be for scientists who model the belts to see whether current theories about how they work can explain this occurrence, and some ideas are already floating to the surface. The belts are thought to be shaped by radio waves traveling through space that accelerate solar wind particles. The waves may originate within the belts themselves or may come from farther out. Either way, they can be affected by a sea of particles that are not fast enough to join the belts and drift like cosmic detritus in orbit around the planet, usually rising from the edge of the atmosphere up to the gap between the two main belts. At the time the third belt appeared, this sea was at a particularly high tide, extending up beyond the region where the third belt appeared.

That has led scientists to piece together this chain of events, some observed, some hypothesized, that might explain how the belt formed: First, the team saw the outer belt shrink almost to nothing, a not-infrequent occurrence, though just why it happens is still unknown. Only a small fringe of the belt remained, the very lower-most part. The outer belt soon coalesced again, but a gap remained between it and the leftover fragment, now, by virtue of its separation, the third belt. Why did it remain separate, rather than being reabsorbed by the outer belt? Perhaps because it was protected by the sea of low-energy particles. “We still need to confirm the theory by modeling it,” says Drew Turner, a researcher in the Earth and Space Sciences Department at UCLA who was not involved in the report. “Until we can reproduce these [events] with models using the theory, we don’t know if it’s actually right.” But it’s a promising start.

For space physicists, this find is just the beginning of what they’ll learn from the Van Allen Probes, whose mission will last at least two years. And for the rest of us, the mysterious third belt is a reminder of how much we still have yet to learn about the universe—even things we thought we’d figured out in 1958.

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9 comments
ChrisThomasWakefield
ChrisThomasWakefield

Pure science rests in three places: in the heart and mind of a graduate fresh out of a university, in words-only published and spoken by scientists and government and corporate sponsors and in the beliefs of armchair scientist wannabes, like you and me. The reason for this is very simple, but complex to explain how it is possible. Essentially there are three reasons for this: the base nature of those who seek positions of power can be described as sociopaths, these are those people who often control the publicity of scientific findings; The next reason is that science requires money and lots of it, so this attracts corporate sponsors who are essentially sociopaths almost by definition. The bright and fine minds of the men and women who work for these governments and corporations often have a life: mortgages, a family and hobbies etc., so are often dependent on their work and the money it provides for them and their family. Other influences are that the incumbent political party requires the funds of corporations to stay in power, the politicians also are dependent on the money and influence their position brings, as well as the possibility of advancement. So if the science data doesn't support the politician, the government department head policy-makers or the corporations image, the study is quietly terminated or the problematic high-minded scientist refusing to cherry-pick the data under pressure is dismissed, or worse. So who wins? The money wins, and the science falls in line.
Of course, then there is the military, don't get me started. Rest assured, what you read on the pages of established science has been pablumized, sanitized and the offending original source elements euphemized. We have nice neat little solar system, exactly as described. History is exactly as it is in the history books. We humans are the only ones in existence anywhere in the Universe and large corporations, agencies such as NASA, NOAA and the UN never have hidden agendas, so all is well and you are in good hands that care about your drinking water, your fresh food supply and your government will never take your land.
Now for those laughing and agreeing with my tongue-in-cheek missive for the mindful, let's look at what is really going on with our Earth:
NASA knows full well Earth is in dire straits and has been since dec 2003 when our temporary solar system member dropped in for its latest visit: Planet X. That's what IRAS was all about in the 80'ies. PX is a very large planet or a small brown dwarf which is highly magnetic. It's magnetic field is what quieted the solar cycles recently and now points somewhat away reactivating the Sun's somewhat normal solar cycle. This same magnetic field is grabbing at the mid-atlantic rift causing the increase in volcanic activity and ground movement around the world: a lateral daily hammering on the continental plates; additionally, the poles of PX "push away" the magnetic north pole once a day (about late morning over the Atlantic) causing the wild weather (Earth moves hundreds of miles in a number of minutes under the atmospheric blanket displacing the mean temperatures with + or - depending where you are on the globe - a wobbling Earth, since 2004) The increase in bolides since the early 2000s are from the tail of Planet X. Global warming Theory was developed to cover for what was known to be coming: a complete boondoggle.
More here:
www.survivingthepoleshift.com
C.W.

Hadrewsky
Hadrewsky

@ChrisThomasWakefield 


You have not one bit of hard evidence, only conspiracy theories. Independent astronomers or any idiot with a decent telescope could provide hard evidence....    Yet you have none/


What I think is that your loathing of the 'sheep' has perverted any critical thinking skill you once had because of your desperation to believe in something only the 'elite' know....


You are as stupidly ignorant as a brain addled 8th grader with a habit of eating lead-based paint chips... And you know nothing of how much raving stupid-talk you spew.

ToddWest
ToddWest

One more reason these HAARP experiments are probably criminal.  Just keep screwing around with your atmosphere great scientists, keep dumping your deadly particulates into the air for your weather experiments, keep that haarp roaring.  When you destroy the only planet we have, you will get what you deserve, mainly the people and the greater than you natural powers that be coming to tear you a new one.....

JenniferBonin
JenniferBonin

@ToddWest Haha.  I suppose you also believe that conspiracy that the HAARP guys are controlling weather and earthquakes, too, huh?  Well, sorry to disappoint you, but they're not actually shooting "deadly particulates" into the air.  And the ionosphere isn't really "weather" as most of us know it.  On the other hand, if you want your car's GPS to work better, the HAARP guys have a lot to do with that.

BobMcDonald
BobMcDonald

NASA knew about this simple fact 39 years ago. It is simply another magnetic field superimposed over the earth's atmosphere. It mingles, but cannot benefit another huge expenditure of selfi$hness on anyone's part.

JenniferBonin
JenniferBonin

@BobMcDonald Wow.  You really hate scientists.  And I hope you also really hate your cell phone, since it's one of the main beneficiaries of this sort of study.