Mitigating satellite trails through retroreflective coatings: A proposal for preserving the night sky

We propose retroreflective coatings on satellites to mitigate sunlight reflections that cause disruptive trails in astronomical observations. By redirecting sunlight back toward the Sun, this approach reduces apparent brightness without creating thermal burdens, while also enhancing satellite tracking capabilities—offering a timely and practical pathway to address impacts from growing satellite constellations. • Current satellite mega-constellations exceed brightness thresholds for astronomy. • Retroreflective coatings can reduce object brightness without thermal burdens. • Retroreflection as a new strategy to protect astronomy and night-sky heritage.