ExPo image of the circumstellar environment of IRC+10216 in polarised intensity (P_l) observed at optical wavelengths 500–900 nm. The intensity scale is logarithmic and the length of the vectors represents a lower limit to the true polarisation degree. North is up and east is to the left. The inset panel shows how unpolarised starlight is scattered by dust in IRC+10216’s circumstellar environment, resulting in linearly polarised light with a direction that is perpendicular to the incident light ray (in the reference frame of the observer).