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Authors	Eric Bu
Responsible
Last Updated	10/12/2025, 12:48:54 PM
Last Author	Kai Berszin

Overall description

Thermal coatings for satellite serve as a passive temperature control system. They manage the satellite's temperature by reflecting a large amount of sunlight and efficiently radiating away the satellite's internal heat, ensuring that sensitive components operate within their ideal thermal range.

Suggested Thermal Coating Solutions and their properties

Solution	Color	Solar Abs (α_s)	Thermal Emittance (ε_t)
AZ-93	White	0.15±0.02	0.91±0.02
A276	White	0.23	0.88-0.91
Optical Solar Reflectors (8-mil quartz mirrors)	-	0.05-0.08	0.80

Sources

• https://www.aztechnology.com/product/1/az-93
• https://www.socomore.com/media/akeneo_connector/asset_files/a/e/aeroglaze_a276_TDS_english.pdf
• http://matthewwturner.com/uah/IPT2008_summer/baselines/LOW%20Files/Thermal/Spacecraft%20Thermal%20Control%20Handbook/04.pdf

Advantages and disadvantages of Thermal Paintings

Both AZ93 and A276 have been used on various spacecraft for decades and have proven to be functional. Their cost is also relatively lower than Optical Solar Reflectors, though still expensive. However, the complicated application process might require the use of an external supplier.

Sources

• https://www.modusadvanced.com/resources/blog/az-93-white-thermal-control-and-electrostatic-dissipative-esd-paint

Advantages and disadvantages of Optical Solar Reflectors

Optical Solar Reflectors generally have a lower Solar Absorptance (α_s) ratio and better endurance in outer space. However, they are more expensive than thermal coatings.