June 14, 2011
Bubbles of Magnetism at the End of the Solar System
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In NASA’s new view of the heliosphere, the magnetic field lines (in red and blue) create a foamy layer of magnetic bubbles at the far edge (credit: NASA)
NASA’s two Voyager spacecraft set out from Earth back in 1977 and have been traveling towards the edge of the solar system ever since. They have now reached the heliopause, the edge of the heliosphere where the solar wind and the Sun’s magnetic field end and the interstellar magnetic field begins. Scientists had long thought that this transition was orderly, with the Sun’s magnetic field lines neatly turning back to reconnect with the Sun. But now NASA scientists are finding that this region of the solar system is far more complex.
Voyager 1 and 2, now about 9 billion miles from Earth, reached this region of odd space in 2007 and 2008, respectively, and started sending back unexpected data. It’s taken some time for scientists to realize what exactly is going on, but the Voyagers appear to be traveling through a foam-like zone of magnetic bubbles, each about 100 million miles across.
As the Sun spins, its magnetic field twists and wrinkles and, far away, bunches up in folds. Within those folds, magnetic field lines twist and cross and reconnect, forming the magnetic bubbles (watch the video below).
Scientists are particularly interested in how these bubbles interact with cosmic rays, subatomic particles that originate in outer space and are a source of radiation (we’re largely shielded here on Earth, but how to shield future space travelers is still an unanswered question). The foam might let cosmic rays pass between the bubbles, but the bubbles might trap the cosmic rays within them.
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The Sun doesn’t spin. It stays in one place. Or so I remember that it does.
The Sun spins, but not quite like Earth; it spins faster at its equator than at its poles.
Spinning is rotation around an internal axis, orbiting is moving around something (like the Earth around the sun). The Earth does both.
Had I the power, I would launch probes ninety degrees parallel to our solar system. Up or down from the plane of our system to escape and realize things from the center of the sun outward, both directions. Gobs of power or trajectory planning would be needed from here, to get there, but once there, it would be like sitting in the center of a merry-go-round or a turntable, from what is understood. Much could be realized from that angle. Thinking there could be a stationary solar system platform to remain within for much observation without the effects of what is known about energy’s within the plane.
Amazing. Given the newfound importance of cosmic rays on global climate (see CERN CLOUD etc) these findings are likely to impact future predictions of global climate, once we learn more.
As it stands, what we don’t know that we don’t know about global climate comprises roughly 90% or more of all that could possibly be known about climate itself. Very difficult to make predictions under those conditions of abject ignorance.
This is pure fantasy. No one has ever properly defined a “magnetic bubble”. Think about it, just for a micro-second, if you are a physicist. As for foamy, perhaps the author using this term is not well informed about cavitation of fluids, be they fluid or gaseous from specially blad.es