2.2.2. Globules and Magnetic Fields
An isolated Bok-type globule is the simplest dusty molecular cloud which can form one star. Little is known about its magnetic field. The distributions of gas and of dust inside the nearby globules are now becoming available, thanks to millimeter and submillimeter telescopes. In particular, the rotation axis of some globules are now known, and have been compared to the polarization angles (parallel to the magnetic field) obtained at optical wavelengths from stars around the globules (but not inside). Kane and Clemens (1996) found that in six globules, there was a trend for the globule's rotation axis to be roughly aligned with the external magnetic field.
As is well known, the distribution of the magnetic field in the densest core of a cloud or globule is unlikely to be an indicator of the magnetic field direction outside of the cloud or globule (e.g., Goodman 1996). The best way to get the direction of the magnetic field inside the globules would be through polarimetric observations of the dust's own emission at extreme infrared wavelengths. Such observations are under way at some telescopes, notably the JCMT.
It is possible that the evolution of a globule or cloud may force an evolution of its magnetic field (shape and strength), at least after a certain age. In this way, later observations may tell us whether a Bok globule is old enough to allow for an evolution of its magnetic fields.