The magnetic field in Lynds 1457: multiband photopolarimetry

We have performed multiband photopolarimetry toward stars behind the molecular cloud L1457 (MBM 12). This cloud is the nearest known molecular cloud (65 pc) and is thought to be contained within the local "hot bubble." The polarization shows a regular structure, indicating that the cloud is threaded by an ordered magnetic field. The wavelength dependence of the polarization seems to indicate that the grains in L1457 have higher indices of refraction than normal for interstellar clouds. However, the wavelength of maximum polarization indicates that their size distribution is close to normal.