Fig. 3: Mean number of satellite trails per exposure as a function of the population of artificial satellites in Earth orbit.
From: Satellite megaconstellations will threaten space-based astronomy
The average number of satellite trails visible in each exposure is shown in relation to both the number of artificial satellites orbiting Earth (lower x axis) and epoch (upper x axis). Blue, SPHEREx; red, Xuntian; purple, ARRAKIHS; black, Hubble Space Telescope. Contours represent the 95% confidence levels for the mean number of trails. Horizontal solid line indicates one trail per exposure critical contamination level; vertical dotted line marks the current number of active and inactive satellites in orbit (15,000 as of March 2025).
