geomagnetic storms. tagged posts

Human activities have been changing near-Earth space and weather. Credit: NASA’s Goddard Space Flight Center/Genna Duberstein

Our Cold War history is now offering scientists a chance to better understand the complex space system that surrounds us. Space weather – which can include changes in Earth’s magnetic environment – are usually triggered by the sun’s activity, but recently declassified data on high-altitude nuclear explosion tests have provided a new look at the mechanisms that set off perturbations in that magnetic system. Such information can help support NASA’s efforts to protect satellites and astronauts from the natural radiation inherent in space.

From 1958 to 1962, the U.S. and U.S.S.R. ran high-altitude tests with exotic code names like Starfish, Argus and Teak...

In connection with violent solar eruptions, large variations occur in electron density in the ionosphere over Greenland, which interferes with GPH navigation signals as well as flight and satellite communication. The figure (right) shows large electron density in red and small density in blue. This phenomenon gives rise to high electron speeds in the ionosphere, exceeding 1,000 metres per second (left) and resulting in violent energy bursts. For the first time ever, researchers from DTU have demonstrated the phenomenon which cannot yet be explained. (Illustration: DTU Space).

New research from DTU, JPL and University of New Brunswick shows that eruptions on the Sun’s surface not only send bursts of energetic particles into Earth’s atmosphere causing disturbances in our planet’s magnetic fi...

(Illustration) At the highest electron energies measured — above 1 megaelectron volt (Mev) — researchers saw electrons in the outer belt only. Credits: NASA Goddard/Duberstein

600 miles from Earth’s surface is the 1st of 2 donut-shaped electron swarms, Van Allen Belts, or radiation belts. Understanding the shape and size of the belts, which shrink and swell in response to incoming radiation from the sun, is crucial for protecting technology in space. Scientists wish to know just which orbits could be jeopardized in different situations.

“The shape of the belts is actually quite different depending on what type of electron you’re looking at,” said Geoff Reeves . “Electrons at different energy levels are distributed differently in these regions...