It is a mystery that seemed to keep astronomers stumped for over three years, but now scientists have cracked the riddle regarding a mysterious ring of particles.
According to a team of astronomers, it is now understood why particles from inside the solar system bounce off a “ribbon” of energy boundary and neutral atoms from that collision stream inward.
The strange band of energy, which astronomers say seems to wrap around the whole of the solar system, creates a sort of energy field that push particles inward. The ribbon of energy was discovered three years ago, the result of NASA’s Interstellar Boundary Explorer (IBEX) mission. Since collection the data, astronomers and scientists around the world have struggled to identify the source of the barrier, and explain why particles seem to be driven back towards the sun.
In a paper published in the Astrophysical Journal, astronomers, through the use of models and theories, have put forth the so-called “retention theory” that for the first time explains the key observation of the unexplained ribbon’s width.
The theory posits that mysterious band of energy exists in a location where neutral hydrogen atoms from the solar wind meet a local galactic magnetic field. Neutral atoms, which are not affected by magnetic fields, become charged ions when their electrons get stripped away, thus beginning the process of gyrating rapidly around magnetic field lines. The result: ions are aimed back toward the sun.
“Think of the ribbon as a harbor and the solar wind particles it contains as boats,” said Nathan Schwadron of the University of New Hampshire and lead author of the study. “The boats can be trapped in the harbor if the ocean waves outside it are powerful enough. This is the nature of the new ribbon model. The ribbon is a region where particles, originally from the solar wind, become trapped or retained due to intense waves and vibrations in the magnetic field.”
While the latest theory is not the first to propose a solution to the galactic puzzle, Schwadron’s theory provided a key point overlooked by astronomers: That rapid rotation creates waves or vibrations in the magnetic field, and the charged ions then become physically trapped in a region by these waves, which in turn would amplify the ion density and produce the broader ribbon seen.
When the theory was tested against a number of models, Schwadron noted that the results were eerily similar to that observed in the data collected three years ago. That said, while scientists have conceded that the theory answers the most important question, a number of questions remain. A major test for the retention theory will be watching how the ribbon changes in step with observed changes in the solar wind, which could present astronomers with another series of strange twists.
The theory could provide astronomers with a better understanding of how the solar system interacts with interstellar space. It could also provide insight into the magnetic fields of the interstellar medium, which astronomers say still remain largely a mystery.
“The ribbon can be used to tell us how we’re moving through the magnetic fields of the interstellar medium and how those magnetic fields then influence our space environment,” said Schwadron.
Of course, the source of the bands itself still remains largely unclear. NASA has yet to announce any future plans aimed at discovering the source of the ribbon itself.