LONG-LIVED HIGH-ENERGY ELECTRONS BETWEEN THE BELTS

This NASA rendering depicts Earth's Van Allen radiation belts and the path of the Van Allen Probe spacecraft, which were launched in August 2012. Data from the spacecraft have confirmed a never-before-seen phenomenon—a long-lived zone of high-energy electrons residing between the inner and outer radiation belts. Credit: NASA illustration

FROM: LOS ALAMOS NATIONAL LAORATORY
Instruments detect never-before-seen phenomenon in Earth’s Magnetosphere

LOS ALAMOS, N.M., March 1, 2013—U.S. researchers, including a trio from Los Alamos National Laboratory, have witnessed the mysterious appearance of a relatively long-lived zone of high-energy electrons stored between Earth’s Van Allen radiation belts.

The surprising findings, discovered by NASA’s Van Allen Probes (formerly known as the Radiation Belt Storm Probes), were outlined Thursday in Science Express and during a press conference at NASA headquarters in Washington, D.C. The research was led by Dan Baker of the University of Colorado, Boulder, Laboratory for Atmospheric and Space Physics.

"Nature keeps on surprising us by producing long-lived harsh environments in space in regions not previously considered," said Los Alamos plasma physicist Reiner Friedel of LANL’s Intelligence and Space Research Division. "This finding may impact the planning of future space missions."

The Van Allen radiation belts — named in honor James Van Allen, who discovered them nearly 50 years ago — are a pair of donut shaped zones of charged particles that surround Earth and occupy the inner region of our planet’s Magnetosphere. The outer belt contains extremely high-energy electrons, while the inner belt is comprised of energetic protons and electrons. The belts have been studied extensively since the dawn of the Space Age, because the high-energy particles in the outer ring can cripple or disrupt spacecraft. Long-term observation of the belts have hinted that the belts can act as efficient and powerful particle accelerators; the recent observations by the Van Allen Probes—a pair of spacecraft launched in August 2012—now seem to confirm this.

Shortly after launch, the spacecraft activated their Relativistic Electron-Proton Telescope (REPT) instruments to measure particles within the belts and their immediate environs. The instrument immediately detected on September 1, 2012, the presence of a stable zone of high-energy electrons residing between the belts. This donut-shaped third ring nestled between the belts existed for nearly a month before being obliterated by a powerful shockwave of particles emanating from center of the solar system.

Such a distinct, long-lasting ring of high-energy electrons had never before been seen by any prior instrument in space or on Earth. The findings suggest that the Van Allen Belts somehow capture and store energetic electrons in a circular path around our home planet, perhaps in much the same way as a cyclotron can capture and store charged particles here on Earth.

"One of the main reasons the Van Allen Probe instruments are seeing these new features are their unprecedented sensitivity and rejection of backgrounds," Friedel said. "As the mission proceeds, we expect further surprises that will challenge our conventional wisdom on the transport, loss and energization processes in these highly energetic electron radiation regions."

In addition to Friedel, Los Alamos research team members include Geoffrey D. Reeves and Michael G. Henderson. The research team is also represented by the Goddard Space Flight Center, University of New Hampshire, The Southwest Research Institute, Dartmouth College, the University of California—Los Angeles, University of Iowa, and The Aerospace Corporation.

MAJOR PROBE LAUNCH TO STUDY RADIATION BELT STORMS

The identical Radiation Belt Storm Probes will follow similar orbits that will take them through both the inner and outer radiation belts. The highly elliptical orbits range from a minimum altitude of approximately 373 miles (600 kilometers) to a maximum altitude of approximately 23,000 miles (37,000 kilometers). PHOTO CREDIT: NASA

　
FROM: LOS ALAMOS NATIONAL LABORATORY
Los Alamos Provides HOPE for Radiation Belt Storm Probes

Spacecraft pair to explore mysterious region where other satellites fear to tread

LOS ALAMOS, NEW MEXICO, August 30,2012—Los Alamos National Laboratory expertise in radiation detection and shielding is poised to help a national team of scientists better understand a mysterious region that can create hazardous space weather near our home planet.

The Helium Oxygen Proton Electron (HOPE) analyzer is one of a suite of instruments that was successfully launched today as part of the Radiation Belt Storm Probe mission—an effort by NASA and the Johns Hopkins University’s Applied Physics Laboratory to gain insight into the Sun’s influence on Earth and near-Earth space by studying our planet’s radiation belt.

The radiation belt—also known as the Van Allen belt in honor of its discoverer, James Van Allen—is a donut shaped soup of charged particles that surrounds Earth and occupies the inner region of our planet’s Magnetosphere. The outer region of the belt is comprised of extremely high-energy electrons, a shower of tiny, negatively charged bullets if you will, that can easily pierce the skin of spacecraft and knock out their electrical components. Because of these hazards, spacecraft routinely avoid the region.

"Today we are boldly going where no spacecraft ever wants to go," said plasma physicist Geoffrey Reeves of Los Alamos National Laboratory’s Intelligence and Space Research Division. "We know we’re going into the riskiest of environments, so we’ve taken the greatest steps ensure the satellites can complete their mission."

Combined with its inner region of energetic protons and electrons, the Radiation Belt is thought to be a product of cosmic rays and charged particles from the Sun carried toward Earth by the solar wind. The energy of particles within the belt constantly changes, and scientists have sought for decades to understand the mechanisms underlying these fluctuations.

Some space scientists originally thought the intensity of the radiation belts was fairly predictable. Conventional thought assumed that radiation energy levels within the belt increased when the belt was hammered by a large solar storm. However, recent observations have shown that radiation energy intensifies only about half the time after a storm interacts with the belt; in fact, about one-quarter of the time, energy within the belt actually decreases on the heels of a solar drubbing, Reeves said.

"We now know that big storms do not necessarily create large amounts of radiation," he said.

Understanding the radiation belt environment and its variability has extremely important practical applications in the areas of spacecraft operations, spacecraft and spacecraft system design, and mission planning and astronaut safety.

To better observe the complex processes in the radiation belts, the RBSP mission is sending a pair of probes to circle the Earth. The probes will orbit at different speeds, allowing researchers to see subtle energy changes from dual vantage points on much shorter time scales than anything available from Earth’s surface.

The Los-Alamos-designed HOPE instrument is part of a subset of instruments aboard the craft that will directly measure near-Earth space radiation particles to understand the physical processes that control the acceleration, global distribution, and variability of radiation belt electrons and ions. One of the things that makes HOPE unique is the instrument’s ability to measure the more subtle, low-energy particles (electrons, hydrogen, and helium and oxygen ions) while under intense fire from the radiation belts’ high-energy particles.

"It’s like measuring the smallest, slowest raindrops in the eyewall of a hurricane," said Herb Funsten, principal investigator for HOPE instrument and chief engineer for Los Alamos’ Intelligence and Space Research Division. "This is a tremendously difficult measurement. We detect atoms and electrons one at a time, and we sort the atoms by their weight. We have to make sure that the high-energy electron bullets that penetrate the instrument walls don’t mess up our measurements."

The ability to successfully design and build an instrument to provide precise measurements under demanding high-energy conditions not only aids the RBSP mission, but can provide useful expertise for future intelligence applications as well.

A dozen instruments aboard the two probes will help unravel mysteries of the Van Allen Belt, but HOPE will be one of the last of the group to switch on. Because of HOPE’s sensitivity to contamination, scientists will give the spacecraft time to complete its thruster firings, and for any remaining trapped gas in the spacecraft and instrument to dissipate before HOPE begins taking measurements.

"We’ll wait for the probe to shed the rest of its spacecraft body odor before we turn on," Reeves said. "Then, all the instruments will work together to solve the radiation belt puzzle. Ultimately we want to make life better here on the ground by making sure all satellite keep working the way they are supposed to."

The RBSP mission is slated to continue for two years. Los Alamos scientists are hoping to begin having preliminary data to share with other space scientists by the end of the year if the mission experiences no complications.

　

ADDITIONAL STORY
FROM: U.S. AIR FORCE 45th Space Wing Supports NASA’s Radiation Belt Storm Probes Launch
8/30/2012 - CAPE CANAVERAL AIR FORCE STATION, Fla. -- The U.S. Air Force's 45th Space Wing provided flawless Eastern Range support for the successful launch of the NASA's Radiation Belt Storm Probes on an Atlas V rocket Aug. 30.

The launch was designed to study the Earth's Van Allen Radiation Belts and probe the influences of the Sun, according to Col. Robert Pavelko, vice commander of the 45th Space Wing.

"Understanding the radiation belt has important practical applications in the areas of spacecraft operations, design and mission planning -- all key to the mission of Air Force Space Command," said Col. Pavelko.

The launch occurred at 4:05 a.m. (EDT) from Space Launch Complex 41 at Cape Canaveral Air Force Station.

A combined team of military, government civilians and contractors from across the 45th Space Wing provided vital support to the RBSP mission, including weather forecasts, launch and range operations, security, safety and public affairs.

The wing also provided its vast network of radar, telemetry, optical and communications instrumentation to facilitate a safe launch on the Eastern Range.

This was the vice commander's first time serving as the Launch Decision Authority and he said he was thoroughly impressed by the preparation of the entire Eastern Range team to "make it happen."

"It's exhilarating to join so many gifted, hard-working teammates -- military, government civilians, and contractors -- all integral to demonstrating the 45th Space Wing is 'The World's Premier Gateway to Space!'" said Col. Pavelko.

Members of the Wing were involved throughout the process of getting the RBSP into orbit.

"What most people don't see is the amount of behind-the-scenes work that goes on among all our mission partners," said 1st. Lt. Tatiana Cornier, a member of the 5th Space Launch Squadron and on-console Atlas V flight commander for the RBSP mission.

"People around the world and here at the Space Coast see the liftoff, which is definitely my favorite part," she said, "but they don't always see all the heavy lifting that goes on prior to launch day to ensure another successful mission. It's awe-inspiring and I'm honored to be a part of this world-class team," she said.

The mission of the 45th Space Wing is one team...delivering assured space launch, range, and combat capabilities for the Nation