The mechanical and optical properties of the thermal control materials on the Hubble Space Telescope (HST) have degraded over the nearly seven years the telescope has been in orbit. Astronaut observations and photographs from the Second Servicing Mission (SM2) revealed large cracks in the metallized Teflon FEP, the outer layer of the multi-layer insulation (MLI), in many locations around the telescope. Also, the emissivity of the bonded metallized Teflon FEP radiator surfaces of the telescope has increased over time. Samples of the top layer of the MLI and radiator material were retrieved during SM2, and a thorough investigation into the degradation followed in order to determine the primary cause of the damage. Mapping of the cracks on HST and the ground testing showed that thermal cycling with deep-layer damage from electron and proton radiation are necessary to cause the observed embrittlement. Further, strong evidence was found indicating that chain scission (reduced molecular weight) is the dominant form of damage to the metallized Teflon FEP.
Analysis of retrieved Hubble Space Telescope thermal control materials
1998
12 Seiten, 19 Quellen
Conference paper
English
Mechanical properties of teflon FEP retrieved from the Hubble space telescope
Tema Archive | 2001
|TIBKAT | 1984
|Online Contents | 1995
|Degradation of Hubble Space Telescope metallized Teflon FEP thermal control materials
Tema Archive | 1998
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