For decades, scientists have tried to solve a vexing problem of outer space weather. At unpredictable times, high-energy particles bombard the Earth and objects outside the Earth’s atmosphere with radiation that can endanger the lives of astronauts and destroy electronic equipment on satellites.
These explosions can even set off showers of radiation strong enough to reach passengers on airplanes flying over the North Pole.
Despite the efforts of scientists, establishing a clear pattern of how and when eruptions will occur has remained difficult to identify.
In an article published in The Astrophysical Journal Letters, authors Luca Comisso and Lorenzo Sironi, from the Department of Astronomy and the Astrophysics Laboratory at Columbia, used computers for the first time to simulate when and how high-energy particles are born in turbulent environments like the Sun’s atmosphere. This new research paves the way for more accurate predictions of when dangerous explosions of these particles will occur.
An old space weather dilemma
“This exciting new research will allow us to better predict the origin of solar energetic particles and improve forecasting models of space weather events, a key goal of NASA and other space agencies and governments around the world,” said Comisso.
In the next two years, he added, NASA’s Parker Solar Probe, the closest spacecraft to the Sun, may be able to validate the paper’s conclusions by directly observing the predicted distribution of high-energy particles that are generated in the outer atmosphere of the Sun. the sun.
In their paper, the researchers demonstrate that, in fact, magnetic fields in the Sun’s outer atmosphere can accelerate ions and electrons to speeds close to the speed of light.
The outer atmosphere of the Sun and other stars consists of particles in the plasma state, a highly turbulent state distinct from the liquid, gaseous, and solid states. Scientists have long believed that the Sun’s plasma generates high-energy particles. But the particles in plasma move so erratically and unpredictably that until now they have not been able to fully demonstrate how and when this happens.
The explosions can even trigger showers of radiation
Using supercomputers at Columbia, NASA and the National Energy Research Scientific Computing Center, Comisso and Sironi created computer simulations that show the exact motions of electrons and ions in the solar plasma. These simulations mimic atmospheric conditions on the Sun and provide the most extensive data yet gathered on how and when high-energy particles will form.
The research provides answers to questions scientists have been investigating for at least 70 years. In 1949, physicist Enrico Fermi began investigating the magnetic fields of outer space as a potential source of the high-energy particles (which he called cosmic rays) that were observed entering the Earth’s atmosphere.
Since then, scientists have suspected that the solar plasma is a major source of these particles, but it has been difficult to prove this definitively.
Most of the observable matter in the Universe is in the plasma state
Comisso and Sironi’s research has implications far beyond our Solar System. The vast majority of observable matter in the Universe is in the plasma state. Understanding how some of the particles that make up plasma can be accelerated to high energy levels is an important new area of research, as energetic particles are commonly observed not only around the Sun, but also in other environments in the Universe, including around black holes and neutron stars.
While Comisso and Sironi’s new work focuses on the Sun, other simulations could be performed in other contexts to understand how and when distant stars, black holes and other entities in the Universe will generate their own bursts of energy.
“Our results focus on the Sun, but can also be considered a starting point to better understand how high-energy particles are produced in more distant stars and around black holes,” said Comisso, RIGHT EurekAlert.