Space IR Telescope Facility (SIRTF) will carry three instruments to explore the sky in the IR: IRAC, IRS, and MIPS. SIRTF detectors have unprecedented sensitivity in all wavelength ranges. The particles, if present in the field of view (FOV) of the telescope, can cause significant imaging problems of the celestial objects if the thermal emission from the particles exceeds the background emission reaching the detector. Far-field particles may be identified as false targets. The near-field particles can light up the entire detector screen so that no other image may be observed while the particle stays in the FOV. Particles may be generated due to telescope aperture cover ejection, due to micrometeoroids colliding with the solar panel, or through other miscellaneous means. If the particle did not have a significant initial velocity component when it first entered the FOV, the only force to drive it out of the FOV is solar pressure. The time taken by a particle to traverse the FOV on account of the solar pressure alone may be several minutes. It is of interest to know the size and frequency of particles which can enter the telescope FOV without causing a substantial loss in the science data.

Date Published: 27 October 1998
PDF: 9 pages
Proc. SPIE 3427, Optical Systems Contamination and Degradation, (27 October 1998); doi: 10.1117/12.328482

Published in SPIE Proceedings Vol. 3427:
Optical Systems Contamination and Degradation
Philip T. C. Chen; William E. McClintock; Gary J. Rottman, Editor(s)