London: Plans to launch reflective satellites and up to 1 million additional spacecraft in low Earth orbit could disrupt human sleep, wildlife, and ecosystems, scientists have warned.

According to Anadolu Agency, the presidents of four international chronobiology societies have expressed concerns that the proposed scale of orbital deployment would significantly alter the natural night-time light environment globally. Charalambos Kyriacou, a geneticist at the University of Leicester and president of the European Biological Rhythms Society (EBRS), cautioned, "We're saying, please think before you go through with this, because this could have global implications for things like food security. Plants need the night. You can't just get rid of it."

Reflect Orbital, a company involved in these plans, aims to beam sunlight onto 5- to 6-kilometer (3.1-3.7-mile) areas "on demand," while Elon Musk's company SpaceX plans to launch up to 1 million satellites for a solar-powered AI network. Ruskin Hartley of DarkSky International noted that while ideas such as mirrors on satellites beaming "sunlight on demand" sound like science fiction, these proposals are indeed very real.

Miroslav Kocifaj of the Slovak Academy of Sciences highlighted that satellite reflections are already increasing night sky brightness and could reach thresholds set to preserve dark skies by 2035. Tami Martino, head of the Canadian Society of Chronobiology, warned that "circadian systems are sensitive to light levels far below what humans typically perceive as bright. If the night sky becomes permanently brighter, the consequences could ripple through ecosystems in ways we do not yet fully understand."