London, May 16
Scientists have long wondered why the hot gas explosions from the sun don’t cool as quickly as expected, and have now used a supercomputer to find out.
When the solar wind hits Earth, it is almost 10 times hotter than expected, with a temperature of around 100,000 to 200,000 ° Celsius. The outer atmosphere of the sun, from which the solar wind originates, is usually one million degrees Celsius.
Using these simulations, the team, led by researchers at University College London (UCL), deduced that the solar wind stays hot longer due to the small-scale magnetic reconnection that forms in the solar wind turbulence.
This phenomenon occurs when two opposing magnetic field lines break and reconnect to each other, releasing huge amounts of energy. It is the same process that triggers large eruptions of the sun’s outer atmosphere.
“Magnetic reconnection occurs almost spontaneously and all the time in the turbulent solar wind. This type of reconnection usually occurs over an area of several hundred kilometers – which is really tiny compared to the vast dimensions of space. using the power of supercomputers, we were able to approach this problem like never before. The magnetic reconnection events that we observe in the simulation are so complicated and asymmetrical that we continue our analysis of these events, ”said lead author Jeffersson Agudelo from UCL.
To confirm its predictions, the team will compare its data with that collected by the European Space Agency’s (ESA) latest flagship mission, Solar Orbiter.
The Solar Orbiter is designed to find the origins and causes of the solar wind and to study how our sun works.
“It’s an incredibly exciting time to combine huge plasma simulations with the latest observations from Solar Orbiter. Our understanding of reconnection and turbulence could take a leap forward by combining our simulations with new data from the Solar Orbiter. “, explained Agudelo. IANS