How did a third radiation belt appear in the Earth's upper atmosphere?

Jun 20, 2013
NASA's Van Allen probes. Credit: JHU/APL

(Phys.org) —Since the discovery of the Van Allen radiation belts in in the Earth's upper atmosphere in 1958, space scientists have believed that these belts consisted of two doughnut-shaped rings of highly charged particles—an inner ring of high-energy electrons and energetic positive ions, and an outer ring of high-energy electrons.

However, in February of this year, a team of scientists reported in the journal Science the surprising discovery of a previously unknown third radiation ring. This narrow ring had briefly circled the Earth between the inner and outer rings in September 2012 and then almost completely disappeared.

How did this temporary radiation belt appear and dissipate?

In new research, the radiation belt group in the UCLA Department of Atmospheric and Oceanic Sciences explains the development of this third belt and its decay over a period of slightly more than four weeks. The research is available in the online edition of the journal Geophysical Research Letters and will be published in an upcoming print edition.

By performing a "quantitative treatment of the scattering of relativistic electrons by electromagnetic whistler-mode waves inside the dense plasmasphere," the investigators were able to account for the "distinctively slow decay of the injected flux" and demonstrate why this unusual third is observed only at energies above 2 mega-electron-volts.

Understanding the processes that control the formation and ultimate loss of such relativistic electrons is a primary science objective of the NASA Van Allen Probe Mission and has important practical applications, because the enormous amounts of radiation the Van Allen belts generate can pose a significant hazard to satellites and spacecraft, as well to astronauts performing activities outside a spacecraft.

The current research was funded by the NASA, which launched the twin Van Allen probes in the summer of 2012.

Explore further: NASA's BARREL mission launches 20 balloons

More information: www.nasa.gov/mission_pages/rbsp/main/index.html

Related Stories

NASA's BARREL mission launches 20 balloons

May 21, 2013

(Phys.org) —In Antarctica in January, 2013 – the summer at the South Pole – scientists released 20 balloons, each eight stories tall, into the air to help answer an enduring space weather question: ...

20 NASA balloons studying the radiation belts

Feb 04, 2013

In the bright, constant sun of the Antarctic summer, a NASA-funded team is launching balloons. There are twenty of these big, white balloons, each of which sets off on a different day for a leisurely float ...

Tiny CREPT instrument to study the radiation belts

Feb 14, 2013

A smaller version of an instrument now flying on NASA's Van Allen Probes has won a coveted spot aboard an upcoming NASA-sponsored Cubesat mission—the perfect platform for this pint-size, solid-state telescope.

The radiation belt storm probes

Aug 31, 2012

(Phys.org)—Since the dawn of the Space Age, mission planners have tried to follow one simple but important rule: Stay out of the van Allen Belts. The two doughnut-shaped regions around Earth are filled ...

Recommended for you

NASA's space station Robonaut finally getting legs

8 hours ago

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Sun emits a mid-level solar flare

Apr 18, 2014

The sun emitted a mid-level solar flare, peaking at 9:03 a.m. EDT on April 18, 2014, and NASA's Solar Dynamics Observatory captured images of the event. Solar flares are powerful bursts of radiation. Harmful ...

Impact glass stores biodata for millions of years

Apr 18, 2014

(Phys.org) —Bits of plant life encapsulated in molten glass by asteroid and comet impacts millions of years ago give geologists information about climate and life forms on the ancient Earth. Scientists ...

The importance of plumes

Apr 18, 2014

The Hubble Space Telescope is famous for finding black holes. It can pick out thousands of galaxies in a patch of sky the size of a thumbprint. The most powerful space telescope ever built, the Hubble provided ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

Tangent2
2.3 / 5 (6) Jun 20, 2013
Gotta love how this article doesn't even mention the HOW this happened. I had to go to the actual archive article to find out, but I'll save the rest of you some time of digging through the article:

"The ring formed on September 3, 2012 during the main phase of a magnetic storm due to the partial depletion of the outer radiation belt for L > 3.5, and this remnant belt of relativistic electrons persisted at energies above 2 MeV, exhibiting only slow decay, until it was finally destroyed during another magnetic storm on October 1."

More news stories

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Cosmologists weigh cosmic filaments and voids

(Phys.org) —Cosmologists have established that much of the stuff of the universe is made of dark matter, a mysterious, invisible substance that can't be directly detected but which exerts a gravitational ...

Ex-Apple chief plans mobile phone for India

Former Apple chief executive John Sculley, whose marketing skills helped bring the personal computer to desktops worldwide, says he plans to launch a mobile phone in India to exploit its still largely untapped ...

Filipino tests negative for Middle East virus

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.