It looks like 11 satellites survived.For 11, SpaceX releases TLEs from launch 2022-010.NORAD has TLEs for 12 satellites, but one is very deep and probably already burned up.at CelestrakPerhaps SpaceX will return to two second-stage burns with a circular orbit.I don't know if that would be safe if the number of satellites stayed the same.
Do we know why 11 of the 49 satellites managed to survive?
SpaceX Starlink lost 38 of 49 satellites after the launch of Group 4-7 in February 2022 due to enhanced neutral density associated with a geomagnetic storm. Based on observations, forecasts, and numerical simulations from the National Oceanic and Atmospheric Administration Space Weather Prediction Center (SWPC), this study provides a detailed analysis of the space weather conditions and neutral density environment during the event. Simulation results suggest that during this minor to moderate geomagnetic storm, the neutral density enhancement was about 50%–125% increase at altitudes ranging between 200 and 400 km. The operational coupled Whole Atmosphere Model and Ionosphere Plasmasphere Electrodynamics physics-based model demonstrates better performance compared to empirical thermospheric neutral density models, one of which was used by the Starlink team. With an increasing number of satellites in low-Earth orbit, it becomes crucial for SWPC to establish suitable alerts and warnings based on neutral density predictions to provide users guidance for preventing satellite losses due to drag and to aid in collision avoidance calculations.
