At https://phys.org/news/2025-09-mission-pickup-ions-solar-earth.html …. do we really understand the amount of energy the solar wind throws at the Earth’s magnetosphere? The latter is Earth’s defence system against harmful solar and cosmic radiation. A new study from the South West Research Institute in the US provides documented evidence from NASAs MMS mission [to the magnetosphere] of what they call ‘pickup ions’ and associated wave activity in the solar wind environment. Pickup ions, or PUIs, are formed when neutral particles flowing through the heliosphere are ionised in the solar wind. They form a distinct plume population dragged along by the solar wind and gyrating around the local magnetic field, They are a distinct plasma population with different characteristics from other particles in the solar wind. PUIs were observed to have a typical velocity distribution absent of any other significant energetic ion or electron population. The wave activity was detected by using magnetic field data from MMS combined with theoretical analysis of the expected wave growth modes based on models of the observed PUIs. The results of the study indicate that PUIs can in fact generate waves in the solar wind near the Earth and this is said to motivate the need for further statistical studies of these processes. It may be that PUIs play a larger role than previously thought, which would have large implications for models of the solar wind throughout the heliosphere. Even more interesting is that it seems PUIs at farther distances from the Sun show the density of them in the solar wind increases.
At https://phys.org/news/2025-09-astrophysicists-sun-year-magnetic-mirrors.html … just as Earth cycles through the seasons so too does the Sun cycle through an 11 year period of magnetic activity. The solar summer is the solar maximum at the peak of the 11 year cycle. Its winter involves a calm period in the cycle – its end time and the beginnings of the next cycle. Spectacular displays of auroras in the night sky over the poles the last year or so are the classic product of solar maximum. Deepak Chahal has a study published this year containingg some of his work in tracking magetic activity in fast rotating stars similar to our Sun in order to better understand how the magnetic fields of stars evolved over time. Younger stars appear to have faster rotation speeds – and stars appear to slow down over time.
The Sun’s seasons are driven by its magentic field. Once every 11 years the magnetic field flips – and north becomes south. During this process solar activity ramps up. Chahal finds that our Sun conforms with the behavior of other stars. There is nothing happening in our solar system which isn’t happening elsewhere in the universe. We are part of the same basic fabric.
At https://phys.org/news/2025-09-mysterious-feature-magnetic-properties-sun.html … this concerns the tachocline, a thin but dynamic layer within the Sun, as exposed by helioseismology. Does it produce the electric fields associated with the Sun?