NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) is a converted 747SP that houses a 2.5 m telescope that observes the sky through an opening in the side of the aircraft. Because it flies at altitudes up to 45,000 feet, SOFIA gets 99.99% transmission in the infrared. Multiple science instruments mount one at a time on the telescope to interpret infrared and visible light from target sources. Ball Infrared Black (BIRB) currently coats everything that the optics sees inside the telescope assembly (TA) cavity in order to eliminate noise from the glow of background sky, aircraft exhaust, and other sources. A reflectometer and emissometer were used to measure and characterize the coatings in terms of their ability to absorb stray light. These measurements were then compared to the BIRB currently used. Though Aeroglaze Z306 showed lower better (lower) reflectance values than Desothane, neither of these coatings showed better reflectance values than the current BIRB. These characterizations help us to determine an improved recipe for TA cavity coating.


Chemical Engineering | Instrumentation | Materials Science and Engineering | Optics | Other Astrophysics and Astronomy | Stars, Interstellar Medium and the Galaxy


Zaheer A Ali

Lab site

NASA Armstrong (Formerly Dryden) Flight Research Center

Funding Acknowledgement

This material is based upon work supported by the S.D. Bechtel, Jr. Foundation and by the National Science Foundation under Grant No. 0952013 and Grant No. 0833353. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the S.D. Bechtel, Jr. Foundation or the National Science Foundation. This project has also been made possible with support of the National Marine Sanctuary Foundation. The STAR program is administered by the Cal Poly Center for Excellence in Science and Mathematics Education (CESaME) on behalf of the California State University (CSU).

Lesson Plan - Infrared Investigations.pdf (759 kB)
Accompanying lesson plan - infrared astronomy



URL: https://digitalcommons.calpoly.edu/star/194


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