PHEBUS

                                                                                                                                  



Phebus Flight Model integrated on Bepi-Colombo spacecraft




Pictures of Summer 2017 during Spare Model calibrations in Paris


                                            
                                            


Pictures of Summer 2013 during Qualification Model calibrations in Padova

    

    

    




Probing of Hermean Exosphere By Ultraviolet Spectroscopy



The space exploration plans of the European Space Agency include new ambitious space missions which foresee the participation also of the Italian Space Agency. The BepiColombo mission will explore the Mercury planet and its environment. Probing of Hermean Exosphere By Ultraviolet Spectroscopy (PHEBUS) is one of the instruments of the payload. It is a double spectrometer for Extreme Ultraviolet (EUV) and Far Ultraviolet (FUV) spectral regions devoted to the characterization of Mercury’s exosphere; its distinctive feature is to work in the EUV region (55-155 nm) allowing for the first time observations of additional species like He, Ar and N. PHEBUS is a CNES French-led instrument implemented in a cooperative scheme involving Japan JAXA (detectors), Russia (scanner mechanism) and ASI-Italy (ground calibration). The Italian Space Agency is supporting the activities at CNR-IFN. Radiometric calibration of Qualification Model (QM) and Flight Model (FM) as well as QM and FM optical components characterization is under the resposability of CNR-IFN. The experimental activities will be perfomed in the cleanroom using dedicated facilities and optical setups. The Italian team contributes also to development of the radiometric model to support the scientific observations during operations.




The ground calibration activities include the characterization of the optical subsystems, the measure of the efficiency and the geometrical acceptance in term of étendue at the full instrument level. The purpose of such calibrations is the development of a full radiometric model in which all the instrument parameters are taken into account. An exhaustive approach that takes into account the polarization state of the light entering into the instrument and its polarization dependence response has been adopted and mathematically formalized in term of the Mueller Matrix theory.

 
 
 



 For questions or general information about I-TECS please email us at i-tecs@pd.ifn.cnr.it