NASA this week revealed that a "chance encounter" with solar wind around Saturn has allowed the Cassini probe to detect particles being accelerated to high energy states. The phenomenon is similar to the acceleration of high-energy cosmic rays found coming from supernova remnants just last week.
The findings, published this week in the journal Nature Physics, show how certain kinds of solar winds can accelerate electrons. NASA in a statement today said that solar wind around Saturn's magnetic field forms a shockwave that Cassini can use to study the particle acceleration effect.
"Cassini has essentially given us the capability of studying the nature of a supernova shock in situ in our own solar system, bridging the gap to distant high-energy astrophysical phenomena that are usually only studied remotely," said Adam Masters, lead researcher on the paper and a researcher at the Institute of Space and Astronautical Science.
The detection of electron acceleration around Saturn came just as a strong shockwave was detected by Cassini. The researchers are looking for "quasi-parallel" shockwaves, which occur when a magnetic field and the direction of the shock are closely aligned.
Shockwaves, such as those from a supernova or solar wind, are common in the universe. When they hit magnetic fields with certain orientations, particles from the shockwave can be accelerated to close the speed of light. These interactions, scientists believe, could be the source of much of the cosmic rays seen in the universe.
(Image courtesy ESA)