June 9, 2011

Edge Of Our Solar System Filled With Bubbles

NASA said on Thursday that its Voyager spacecraft has helped to show that the edge of our solar system may not be smooth, but filled with a turbulent sea of magnetic bubbles.

Scientists found the sun's distant magnetic field is made up of bubbles about 100 million miles wide. 

NASA said the bubbles are created when magnetic field lines reorganize, and the new model suggests the field lines are broken up into self-contained structures disconnected from the solar magnetic field.

The Voyager spacecraft, which are about 10 billion miles away from Earth, are traveling in a boundary region.  This area consists of solar wind and magnetic field that affect material expelled from other stars in our corner of the Milky Way galaxy.

"The sun's magnetic field extends all the way to the edge of the solar system," astronomer Merav Opher of Boston University said in a statement. "Because the sun spins, its magnetic field becomes twisted and wrinkled, a bit like a ballerina's skirt. Far, far away from the sun, where the Voyagers are, the folds of the skirt bunch up."

Scientists will be able to explain how galactic cosmic rays enter our solar system once they understand the structure of the sun's magnetic field.  NASA said this will also help scientists define how the star interacts with the rest of the galaxy.

The new discovery originates from an instrument aboard Voyager that measures energetic particles.  Investigators are studying more information and hoping to find signatures of the bubbles in the Voyager magnetic field data.

"We are still trying to wrap our minds around the implications of the findings," said University of Maryland physicist Jim Drake, one of Opher's colleagues.


Image Caption: Old and new views of the heliosheath. Red and blue spirals are the gracefully curving magnetic field lines of orthodox models. New data from Voyager add a magnetic froth (inset) to the mix. Credit: NASA


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