A gigantic ribbon of energy and charged particles at the edge of the solar system could help direct the interstellar magnetic field, according to physicists.
The feature was first spotted by a NASA spacecraft, Interstellar Boundary Explorer, or IBEX, in 2009. That spacecraft orbits the Earth.
Effects of the ribbon on interstellar magnetic fields are determined by comparing IBEX findings with observations taken from ground-based telescopes.
What astronomers found was the ribbon, created from the interaction of the solar wind with space dust, lies at right angles to the interstellar magnetic field. Cosmic rays, created in supernovas, travel along the magnetic fields between stars. High -energy particles from the Sun travel outward from our home star, through the heliosphere. When the influence of the Sun begins to give way to the interstellar medium, these particles are pushed by cosmic rays between the stars. This slows down the travel of the solar wind. Where this happens is called the heliosheath, and this point is usually considered the edge of the solar system.
The interstellar medium consists of positively-charged ions, electrons carrying a negative charge, neutral atoms, and dust. Matter this far from the Sun is dominated by electromagnetic forces. Paths of charged particles are warped by the magnetic field of the ribbon. Once in a while, a positive ion will strike a neutral atom, gathering an electron. This negates the charge of the first particle, rendering it electrically neutral. Since it is no longer charged, the particle no longer flows in the magnetic field. A few of these head toward the Earth, and are picked up by IBEX.
The interstellar ribbon could act as a road map in the sky, directing cosmic rays around our solar system. By studying this giant magnetic ribbon, astrophysicists may be able to answer a question that has plagued astronomy for decades. More cosmic rays are received from one side of the Sun than from the other. Until now, the cause of this behavior was unknown.
"What I always have been trying to do was to establish a clear connection between the very high-energy cosmic rays we're seeing (from the ground) and what IBEX is seeing," Nathan Schwadron of the University of New Hampshire who headed the study, told Space.com
Astrophysicists believe this new research may assist them in unwrapping the nature of the edge of our solar system. Only one spacecraft, Voyager 1, has so far reached the heliosheath. Findings from the spacecraft can be interpreted a number of ways. Researchers are still unable to determine if the most distant man-made object is yet in interstellar space.
Details of the interstellar ribbon study were published in the journal Science Express.
