University of Wisconsin, Madison | 2019 Jun 10
A new, more accessible and much cheaper approach to surveying the topology and strength of interstellar magnetic fields — which weave through space in our galaxy and beyond, representing one of the most potent forces in nature — has been developed by researchers at the University of Wisconsin–Madison.
Together with gravity, magnetic fields play a major role in many of the astrophysical processes — from star formation to stirring the massive dust and gas clouds that permeate interstellar space — that underpin the structure and composition of stars, planets and galaxies. On the galactic scale, magnetic fields dominate the acceleration and propagation of cosmic rays, and play an important role in transferring heat and polarized radiation.
What’s more, the polarized radiation that arises from galactic magnetic fields exceeds by orders of magnitude that of the Cosmic Microwave Background (CMB), the relic radiation of the first moments of the universe. The next milestone in understanding the origin of the universe, some scientists believe, requires measuring the CMB’s polarized radiation. Importantly, unraveling the topology of the intervening magnetic fields between Earth and the CMB will be a necessary step to reliably obtain those data.
But despite their importance and pervasive influence, interstellar magnetic fields represent one of the final frontiers of astrophysics. Little is known about them, in large part, because they are exceedingly difficult to study. ...
Magnetic Field Morphology in Interstellar Clouds with the Velocity Gradient Technique ~ Yue Hu et al
- Nature Astronomy (online 10 Jun 2019) DOI: 10.1038/s41550-019-0769-0