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In this report, we introduce and justify the urgent need for SatHub, a coordinated observing effort for satellite constellations that encompasses multiple aspects of work. In addition, the Observations Working Group identified a number of additional considerations that must be taken into account.

As the Sun approaches its next maximum activity level in 2024 or 2025, space weather events that affect the LEO environment will become more frequent. Increased solar activity will result in increased atmospheric scale height, which causes increased drag on LEOsats. In periods of greater solar activity, LEOsats will have to correct their altitudes much more frequently than they currently do in order to maintain operating altitudes.

Much more worryingly, extreme space weather events — which are most common during solar maximum — like coronal mass ejections and radio bursts could cause communication disruptions with LEOsats, and the high-energy charged particles could cause satellites to enter safe mode or even become fully disabled. With thousands of satellites in similar orbits that are relying on active collision avoidance, even a short window of time where many satellites are disabled or in safe mode could prove disastrous. Operators need to plan for this in order to avoid catastrophic collisions.

The NIR laser communication wavelength is 1.550 nm, which is within the astronomical photometric H band (1.490–1.780 nm). Because communications require generation of the signal, leakage (direct line of sight or scattering) from satellite cross-links and down-links could cause a significant impact on astronomical data collections. Given the multi-billion dollar nature of the laser communications industry, the path forward may require a redefinition of the H band.

Various proposals have been circulated to add flashing light emitting diodes, either in the optical or the NIR, to all satellites as a means of positive identification or as a form of advertising. While these might or might not be visible to the unaided eye, the impact on images obtained by modest to large-aperture Rh