Clashing magnetic fields blast solar winds

From the abc.net.au article:
The solar wind paints earth’s skies with auroras and pushes solar sails through space. But just how the streams of electrically charged particles flow out of the sun has been a mystery until now.

Like most phenomena associated with stars, the process is violent, international scientists have discovered.

Pockets of hot gases on the sun’s surface, which pool around bright knots of magnetic activity, spurt out into space when the sun’s snarling, snaking magnetic fields collide.

“[The phenomenon] has been debated for many years,” says Professor Louise Harra, a University College London researcher who this week unveiled the sun’s secret at a Royal Astronomical Society meeting in Belfast.

Harra planned to show images from the orbiting Hinode spacecraft showing magnetic fields linking two bright spots on the sun.

The spots are nearly 500 million kilometres apart, a distance equivalent to 40 earths placed side by side.

When the magnetic fields smashed into each other, charged gases flew out in all directions, forming the solar wind.

“It is fantastic to finally be able to pinpoint the source,” Harra says, adding that the next step is to figure out how the wind is transported through the solar system.

The solar wind permeates the solar system, defining its shape and scope, as it blasts along at 200 kilometres per second on the slow days.

During snappier binges, strong gusts blasting into earth’s magnetic bubble can have a myriad ramifications from the beautiful and benign aurora above earth’s poles to the shutdown of power and communications systems on the planet.

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Voyager 2 Proves Solar System Is Squashed

From voyager.jpl.nasa.gov:
San Francisco, CA. – NASA’s Voyager 2 spacecraft has followed its twin Voyager 1 into the solar system’s final frontier, a vast region at the edge of our solar system where the solar wind runs up against the thin gas between the stars.

However, Voyager 2 took a different path, entering this region, called the heliosheath, on August 30, 2007. Because Voyager 2 crossed the heliosheath boundary, called the solar wind termination shock, about 10 billion miles away from Voyager 1 and almost a billion miles closer to the sun, it confirmed that our solar system is ” squashed” or ” dented”- that the bubble carved into interstellar space by the solar wind is not perfectly round. Where Voyager 2 made its crossing, the bubble is pushed in closer to the sun by the local interstellar magnetic field.

“Voyager 2 continues its journey of discovery, crossing the termination shock multiple times as it entered the outermost layer of the giant heliospheric bubble surrounding the Sun and joined Voyager 1 in the last leg of the race to interstellar space.” said Voyager Project Scientist Dr. Edward Stone of the California Institute of Technology, Pasadena, Calif.

The solar wind is a thin gas of electrically charged particles (plasma) blown into space by the sun. The solar wind blows in all directions, carving a bubble into interstellar space that extends past the orbit of Pluto. This bubble is called the heliosphere, and Voyager 1 was the first spacecraft to explore its outer layer, when it crossed into the heliosheath in December 2004. As Voyager 1 made this historic passage, it encountered the shock wave that surrounds our solar system called the solar wind termination shock, where the solar wind is abruptly slowed by pressure from the gas and magnetic field in interstellar space.

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