Interstellar Magnetic Fields

The interstellar medium is a thin gruel of gas and dust that occasionally clumps together, eventuating in star formation. Magnetic fields mystically permeate the interstellar medium and shape the cosmological future.

The interstellar medium (ISM) comprises the matter between galactic star systems. It is a sparse mixture of mostly hydrogen, a sprinkling of helium, and traces of carbon, oxygen, and nitrogen. 99% of the ISM is low-density gas and 1% is dust.

Despite there being scant matter in space and it being very cold, there is tremendous turbulence and intense magnetic fields in interstellar space. The abiding energetic vigor of the ISM is a mystery.

Astronomer Juan Diego Soler: “Magnetic fields play a significant role in structuring the interstellar medium in and around molecular clouds.” Powerful magnetic fields in the ISM maintain a delicate balance between pressure and gravity which flows like rivers and guides the birth of stars. Matter within the interstellar medium is coupled to the surrounding magnetic field in such a way that the matter can only move along magnetic field lines, creating conveyor belts of field-aligned matter. How interstellar magnetic fields maintain themselves and guide the matter under their sway with such finesse is not understood.


Juan D. Soler, “Using Herschel and Planck observations to delineate the role of magnetic fields in molecular cloud structure,” Astronomy & Astrophysics (September 2019).

Magnetic fields play role in structuring interstellar medium in and around star-forming clouds: study,” Sci-News (19 November 2019).

M. Opher et al, “A strong, highly-tilted interstellar magnetic field near the Solar System,” Nature (24 December 2009).

Telemachos Ch. Mouschovias, “Interstellar magnetic fields,” Advances in Space Research 2(12): 71–80 (1982).