Too many satellites won't let you see the sky.

 Light pollution arises not only from artificial nocturnal illumination but also from space debris and man-made satellites congesting the low Earth orbit, reflecting solar light. This poses a significant hindrance to astronomical research, as it prevents scientists from fully exploiting their telescopes' capabilities. In other words, an excess of satellites obstructs celestial observation.

A galaxy observed by the Hubble Space Telescope has been ruined by an artificial satellite. Credits: NASA/ESA/Kruk et al. 2023.

The Case of Hubble Images

The issue in question also impacts space telescopes situated within the low Earth orbit. For instance, upon examining the archive of observations conducted by Hubble from 2002 to 2021, it was discovered that nearly three percent of its images contained at least one trail left by an artificial satellite. Without limiting the pace of launching new satellites, it is estimated that, by 2030, this fraction could assume a value ranging between twenty and fifty percent.

Consequently, both the trails in telescope images and the increased brightness of the sky necessitate additional observations with extended durations. Furthermore, competition for each telescope's time will intensify, disadvantaging research institutions with fewer financial resources.

Sources: Nature, Nature.