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A leading space scientist has called to question the validity of human spaceflight, suggesting that sending astronauts outward from Earth is outdated, too costly, and the science returned is trivial.The human space flight critic is no stranger to space -- in fact he's a pioneer in the space science arena from the premier days of satellite orbiting Earth.James van Allen, Regent Distinguished Professor at the University of Iowa, is the noted discoverer ofradiation belts encircling Earth. His seminal finding -- labeled the Van Allen radiation belts -- stemmed from the scientist's experiment that flew on Explorer1, America’s first satellite to...

The radiation belts around Earth are loaded with dangerous protons and electrons that can damage spacecraft. Now researchers are launching experiments to see if they can clear away the high-energy particles that pose the hazard by blasting them with radio waves.When humans began exploring space, the first major find was the Van Allen radiation belts, doughnut-shaped zones of magnetically trapped, highly energetic charged particles. The Van Allen belts consist mainly of two rings: The inner belt starts roughly 1000 kilometers above Earth’s surface and extends up to 9600 km, while the outer belt stretches from about 13 500 to 58...

Using NASA’s Van Allen Probes, new research reveals that the Van Allen radiation belts contain a nearly impenetrable barrier that prevents the fastest, most energetic electrons from reaching Earth.The Van Allen belts are a collection of charged particles, gathered in place by Earth’s magnetic field. They can wax and wane in response to incoming energy from the sun, sometimes swelling up enough to expose satellites in low-Earth orbit to damaging radiation. The discovery of the drain that acts as a barrier within the belts was made using NASA’s Van Allen Probes, launched in August 2012 to study the region. A...

The South Atlantic Anomaly is a location in the southern Atlantic where the innermost portions of the natural zone of energetic charged particles encircling Earth, known as the Van Allen radiation belt, makes its closest approach to the planet. The resulting outflow of energized particles produces a higher yield of ionizing radiation detectable by satellites orbiting Earth. Our planet’s geomagnetic field undergoes constant changes that result from the activity occurring in the Earth’s core, which current models aren’t capable of easily predicting. Because of this, the World Magnetic Model can only offer a good estimate of the Earth’s geomagnetic activity...

A team led by the University of Colorado Boulder has discovered an invisible shield some 7,200 miles above Earth that blocks so-called “killer electrons,” which whip around the planet at near-light speed and have been known to threaten astronauts, fry satellites and degrade space systems during intense solar storms. The barrier to the particle motion was discovered in the Van Allen radiation belts, two doughnut-shaped rings above Earth that are filled with high-energy electrons and protons, said Distinguished Professor Daniel Baker, director of CU-Boulder’s Laboratory for Atmospheric and Space Physics (LASP). ... The latest mystery revolves around an “extremely sharp”...

Abigail and Dr. James Van Allen and his wife, Abigail, met “by accident” when she backed into his car at a stoplight in Baltimore. He scowled, but said nothing. When she ran into him again a few minutes later at the applied physics lab at Johns Hopkins University where they worked, she said, “Who do you think you are, throwing those dirty looks?” He called her the following Sunday to go bicycling. The Van Allens married on Oct. 13, 1945, in Southampton, Long Island. They lived right outside Washington, D.C., until 1951 when Van Allen accepted the position of head...

Killer Electrons From Outer Space By Saswato R. Das Accurate space-weather forecasts could come from knowing the cause of superfast electrons in the Van Allen belts Image: NASA Glenn Research Center 31 August 2007—Researchers at Los Alamos National Laboratory, in New Mexico, say they have solved the mystery of satellite-zapping “killer electrons” that are sometimes produced in Earth’s outer atmosphere. These highly energetic electrons—strong enough to damage electronics and human tissue—pose a danger to spacecraft, satellites, and astronauts. For many years, the mechanism by which they are produced has remained little understood, in spite of physicists’ attempts at solving this...