The Impact of Orbital Data Centers on the NSF-DOE Vera C. Rubin Observatory

Abstract

As the NSF-DOE Vera C. Rubin Observatory begins its Legacy Survey of Space and Time (LSST), satellite operators are racing to launch Orbital Data Center (ODC) satellites into low-Earth orbit. We present an impact assessment of a simulated $\sim$1 million ODC satellite constellation, arranged per recent filings across two low-Earth and two Sun-synchronous orbit regimes, on one year of Rubin Observatory LSST observations. Our six-stage sequential pipeline combines orbit propagation, field-of-view matching, observer-frame geometry, brightness modeling, surface-brightness calculations, and pixel-loss estimates. We find that on a given night, up to 80% of LSST pointings would contain at least one illuminated ODC satellite streak, depending on the time of year. The yearly average of contaminated exposures is closer to 20%, due to seasonal visibility variations and bright satellite streaks being most prominent near twilight. Sun-synchronous ODCs disproportionately contaminate due to preferential illumination geometry. The ODC satellite brightness distribution is multi-modal, where solar panel specular reflection can appear as bright as 2-4 AB mag ($μ_g \approx 9-11$ mag arcsec$^{-2}$), while diffuse reflections more typically reach 6 AB mag ($μ_g \approx 13-14$ mag arcsec$^{-2}$). Even at 10% deployment, the constellation would still produce widespread visible streak contamination throughout the year. ODC satellites would also drastically increase sky brightness -- by more than 1000% near twilight with no Moon. Launching and operating ODC satellites at this scale would significantly harm LSST science, including typical 5-10% nightly mean pixel losses near twilight, even if multiple mitigation strategies are implemented.