Poster title: Spectropolarimetry of the scattered sunlight: from calibrations to the diagnostic of planetary atmospheres

Poster abstract: It is well known that continuum twilight is highly polarised. It is much less known that the sky exhibits a 
wealth of spectropolarimetric features due to our atmosphere which may have a negative impact on high-accuracy 
polarimetric measurements. We will present some fascinating examples of low to mid-resolution spectropolarimetry of 
skylines obtained during twilight calibrations.