Magnetic field’s role in Galactic bubble formation

Ascertain the role of the interstellar magnetic field in the formation of Galactic bubbles, specifically the Local Bubble and the North Polar Spur, and determine whether magnetic processes are primary drivers or secondary influences in their creation and evolution.

Background

One proposed pathway for the Radcliffe wave’s origin involves shock waves from multiple supernovae and associated stellar winds during the formation of superbubble structures such as the Local Bubble and the North Polar Spur. Understanding whether and how magnetic fields contribute to these processes is pivotal for interpreting large-scale vertical oscillations and coherent filaments in the local disk.

This review places particular emphasis on magnetic influences, including Parker instability as a candidate mechanism, and discusses recent observational indications of alignment between magnetic field lines and the Radcliffe wave. Nonetheless, the specific role of magnetic fields in bubble formation remains unresolved and is highlighted as a key open question.

References

According to a number of authors [17, 18], the Radcliffe wave could have arisen as a result of the impact of shock waves from several supernovae and their stellar winds during the formation of the Local Bubble or North Polar Spur. However, the most important question about the role that the magnetic field plays in the formation of bubbles remains open to this day [19].

— Place of the Radcliffe Wave in the Local System  (2510.25570 - Bobylev et al., 29 Oct 2025) in Introduction