COMPARISON OF RESULTS FROM POST-FLIGHT INVESTIGATIONS ON FEPRETRIEVED FROM THE HUBBLE SPACE TELESCOPE SOLAR ARRAYS AND LDEF

摘要

Teflon? FEP is used on the Hubble Space Telescope(HST) as outer layer of the multilayer insulationblankets. During the space shuttle servicing missions(SM) to HST through thickness cracks were observed inthe FEP layers. Material that was brought to Earth forinvestigation showed signs of severe degradation.During SM3B, the last servicing mission to HST inMarch 2002, the second pair of ESA built solar arrays(HST/SA2) was demounted after 8.25 years in spaceand brought back to earth. Samples were taken from thesolar array and investigated for surface and bulkdegradation.Therefore the solar absorptance α S and the normalemittance ε N were measured and tensile properties andsamples thicknesses evaluated. Results of these tests arecompared to analyses of samples retrieved from theLong Duration Exposure Facility (LDEF), from the HSTsolar array 1 (HST/SA1) and sample specimen exposedto thermal cycling, soft x-ray and VUV radiation inESTEC. The new results showed unprecedenteddegradation and confirmed solar radiation – especiallyX-rays from solar flares - as important contributor to thebulk degradation of FEP.