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.


 
 

 
Image courtesy of NASA/JPL-Caltech/Univ. of Arizona

NASA’s Mars Curiosity rover arrives at Martian mountain

NASA’s Mars Curiosity rover has reached the Red Planet’s Mount Sharp, a Mount-Rainier-size mountain at the center of the vast Gale Crater and the rover mission’s long-term prime destination. “Curiosity n...
 
 

NASA announces 2014 aeronautics scholarship recipients

NASA has selected 20 students from across the nation to receive the agency’s Aeronautics Scholarship for the 2014-2015 school year. This scholarship program, which is in its seventh year, is designed to assist undergraduate and graduate students enrolled in fields of study related to aeronautics. Recipients were selected from hundreds of applications to the program....
 
 
NASA photograph by Dan Casper

NASA’s Orion spacecraft nears completion, ready for fueling

NASA photograph by Dan Casper The Orion crew module, stacked atop its service module, moved out of the Neil Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center in Florida on Sept 11. Orion was transporte...
 

 

NASA awards cross-track infrared sounder instrument for the JPSS-2

NASA has awarded a sole source contract modification to Exelis, Inc., Geospatial Systems, of Fort Wayne, Ind., for the Cross-track Infrared Sounder Instrument for flight on the Joint Polar Satellite System-2 mission. This is a cost-plus-award-fee modification in the amount of $221 million. This action extends the period of performance of the contract from November...
 
 
NASA photograph

NASA unveils world’s largest spacecraft welding tool for Space Launch System

NASA photograph A 16mm fisheye lens was used to show a wide angle view of the Vertical Assembly Center at NASA’s Michoud Assembly Facility in New Orleans at a ribbon-cutting ceremony Sept 12. The VAC is the largest spacecraft...
 
 
boeing-satellite

Boeing receives first order for 502 Phoenix small satellite

EL SEGUNDO, Calif. – Boeing has received its first commercial order for the 502 Phoenix small satellite from HySpecIQ of Washington, D.C. The satellites will carry the commercial remote sensing industry’s first high...
 




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>