When we dive deep into the theoretical models of star formation, we think of ingredients needed for this and the factors affecting this process considerably. Magnetic fields (B-fields, hereafter) are found to play a crucial in the process of star-formation. Not only formation of sun like stars but in intermediate and high-mass star formation too. B-fields are the unsolved piece of puzzle in the formation of stars. We do see their effects on different scales but we have a very limited knowledge till date. The reason is that B-fields are most difficult to measure compared to other physical properties such as mass, temperature etc. If they are strong, they can deflect or even oppose gas flowing into a young stellar core as it collapses under the influence of gravity. If they are moderate in strength, however, they act more flexibly and guide the flow, but don’t prevent it. Early measurements of field strengths in molecular clouds were based on radiation from molecules whose energy levels are sensitive to magnetic field strengths. Polarimetry has been found to be the best tool to investigate these B-fields in different environments. More recent observations with stronger signals measured the polarized radiation from dust grains aligned with the magnetic field. These observations obtain the field strength from the changes in field direction across the cloud map.
