Space

March 1, 2013

NASA’s Van Allen probes reveal a new radiation belt around Earth

NASA’s Van Allen Probes mission has discovered a previously unknown third radiation belt around Earth, revealing the existence of unexpected structures and processes within these hazardous regions of space.

Previous observations of Earth’s Van Allen belts have long documented two distinct regions of trapped radiation surrounding our planet. Particle detection instruments aboard the twin Van Allen Probes, launched Aug. 30, quickly revealed to scientists the existence of this new, transient, third radiation belt.

The belts, named for their discoverer, James Van Allen, are critical regions for modern society, which is dependent on many space-based technologies. The Van Allen belts are affected by solar storms and space weather and can swell dramatically. When this occurs, they can pose dangers to communications and GPS satellites, as well as humans in space.

“The fantastic new capabilities and advances in technology in the Van Allen Probes have allowed scientists to see in unprecedented detail how the radiation belts are populated with charged particles and will provide insight on what causes them to change, and how these processes affect the upper reaches of Earth’s atmosphere,” said John Grunsfeld, NASA’s associate administrator for science in Washington.

This discovery shows the dynamic and variable nature of the radiation belts and improves our understanding of how they respond to solar activity. The findings, published Thursday in the journal Science, are the result of data gathered by the first dual-spacecraft mission to fly through our planet’s radiation belts.

The new high-resolution observations by the Relativistic Electron Proton Telescope (REPT) instrument, part of the Energetic Particle, Composition, and Thermal Plasma Suite (ECT) aboard the Van Allen Probes, revealed there can be three distinct, long-lasting belt structures with the emergence of a second empty slot region, or space, in between.

“This is the first time we have had such high-resolution instruments look at time, space and energy together in the outer belt,” said Daniel Baker, lead author of the study and REPT instrument lead at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado in Boulder. “Previous observations of the outer radiation belt only resolved it as a single blurry element. When we turned REPT on just two days after launch, a powerful electron acceleration event was already in progress, and we clearly saw the new belt and new slot between it and the outer belt.”

Scientists observed the third belt for four weeks before a powerful interplanetary shock wave from the sun annihilated it. Observations were made by scientists from institutions including LASP; NASA’s Goddard Space Flight Center in Greenbelt, Md.; Los Alamos National Laboratory in Los Alamos, N.M.; and the Institute for the Study of Earth, Oceans, and Space at the University of New Hampshire in Durham.

Each Van Allen Probe carries an identical set of five instrument suites that allow scientists to gather data on the belts in unprecedented detail. The data are important for the study of the effect of space weather on Earth, as well as fundamental physical processes observed around other objects, such as planets in our solar system and distant nebulae.

“Even 55 years after their discovery, the Earth’s radiation belts still are capable of surprising us and still have mysteries to discover and explain,” said Nicky Fox, Van Allen Probes deputy project scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. “We thought we knew the radiation belts, but we don’t. The advances in technology and detection made by NASA in this mission already have had an almost immediate impact on basic science.”

The Van Allen Probes are the second mission in NASA’s Living With a Star Program to explore aspects of the connected sun-Earth system that directly affect life and society. Goddard manages the program. The Applied Physics Laboratory built the spacecraft and manages the mission for NASA.

 




All of this week's top headlines to your email every Friday.


 
 

 

Headlines July 28, 2014

News: U.S. has lost track of weapons given to Afghanistan - The United States supplied almost three quarter of a million weapons to Afghanistan’s army and police since 2004, but the military cannot track where many of those arms have gone, a new report found. Bill to improve VA has $17 billion price tag - A bipartisan...
 
 

News Briefs July 28, 2014

Marines seek authorization for dolphin deaths The Marine Corps is asking for a five-year authorization from the National Marine Fisheries Service for incidental deaths of bottlenose dolphins during training exercises at a bombing and target range. The Sun Journal of New Bern, N.C., reports that Connie Barclay of the National Oceanic and Atmospheric Administration says...
 
 
Army photograph by David Vergun

Senior leaders explain Army’s drawdown plan

Army photograph by David Vergun No commander is happy when notified that a soldier from his or her command has been identified for early separation. But commanders personally notify those Soldiers and ensure participation in th...
 

 

Northrop Grumman awarded mission support services contract

The U.S. Army awarded Northrop Grumman a cost-plus-fixed-fee contract, with a potential value of $205 million, to continue providing mission logistics services in support of combat brigades training at the National Training Center in Fort Irwin, Calif. The contract covers one base year and two one-year options. Support will include the full range of mission...
 
 
Lockheed Martin photograph by Beth Groom

F-35 Rollout Marks U.S.-Australia Partnership Milestone

Lockheed Martin photograph by Beth Groom Royal Australian Air Force Air Marshal Geoff Brown delivers his remarks at the roll out ceremony for Australia’s first F-35. The official rollout of the first two F-35 Lightning II...
 
 
NASA/JPL-Caltech image

NASA’s Mars spacecraft maneuvers to prepare for close comet flyby

NASA/JPL-Caltech image This graphic depicts the orbit of comet C/2013 A1 Siding Spring as it swings around the sun in 2014. On Oct. 19, the comet will have a very close pass at Mars. Its nucleus will miss Mars by about 82,000 m...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>