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A mysterious phenomenon detected by space probes has finally been explained, thanks to a massive computer simulation that was able to precisely align with details of spacecraft observations. The finding could not only solve an astrophysical puzzle, but might also lead to a better ability to predict high-energy charged particles which affects Earth.

A good example of what appears to be a shift in the understanding of the Sun-Earth connection. On Feb. 27th, the Earth experienced a geomagnetic storm. But where did it come from? It wasn't solar flares, nor an escalation of sunspots, but a stream of moderate CMEs (coronal mass ejections) have unleashed over the past five days.

Yesterday and early today, more beautiful auroras appeared over Scandinavia, Iceland, Greenland and Finland. What caused this geo-magnetic storm and is something different in this cycle than previous ones?

Yes, this cycle does appear to have some tricks up its sleeve. What is different is the method of release and I would also suggest - a difference in the method of generating plumes of electrons and protons from the Sun. One immediate question comes to mind - does the shift in our galaxy and hence solar system play a role?

A just released study of the moons craters suggests newer larger craters were caused by the dislodging of the known asteroid belt sending large bolides into the inner solar system by shifts in the orbits of the giant planets.

Could it be as part of a larger cycle, the Sun, Galaxy, and Solar System play-out some unfamiliar schism which may better reflect what ancient text tells us of this time?

This brief pulse of impacting objects was due to gravitational disturbances caused by the reorganization of the giant planets as their orbits changed. Nectaris, a crater close to the Apollo 16 landing site, appears to have recorded the spike in asteroid impacts during the "lunar cataclysm."
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Jan Egedal, an associate professor of physics at MIT and a researcher at the Plasma Science and Fusion Center, that as the solar wind stretches Earth's magnetic-field lines, the field stores energy like a rubber band being stretched. When the parallel field lines suddenly reconnect, they release that energy all at once - like releasing the rubber band. That release of energy is what propels electrons with great energy (tens of thousands of volts) back toward Earth, where they impact the upper atmosphere. This impact is thought, directly or indirectly, to generate the glowing upper-atmosphere plasma called the aurora, producing spectacular displays in the night sky.

What had puzzled physicists is the number of energetic electrons generated in such events. According to theory, it should be impossible to sustain an electric field along the direction of the magnetic field lines, because the plasma (electrically charged gas) in the magnetotail should be a near-perfect conductor. But such a field is just what's needed to accelerate the electrons. And, according to the new simulation, the volume of space where such fields can build up can, in fact, be at least 1,000 times larger than the theorists had thought possible - and thus large enough to explain the observed electrons.
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Egedal had initially proposed a theory to explain this large-scale acceleration of electrons in Earth's magnetotail - a vast and intense magnetic field swept outward from Earth by the solar wind - but until the new data was obtained from the computer simulation, "it used to be people said this was a crazy idea. Thanks to the new data, I don't get that anymore."

The simulation shows that an active region in Earth's magnetotail, where "reconnection" events take place in the magnetic field, is roughly 1,000 times larger than had been thought. This means a volume of space energized by these magnetic events is sufficient to explain the large numbers of high-speed electrons detected by a number of spacecraft missions, including the Cluster mission.