Starlink's Gen 3 System Faces Opposition From Radio Astronomers

Key Points:

• The US National Science Foundation's National Radio Astronomy Observatory (NRAO) opposes SpaceX's Starlink Gen 3 satellite proposal due to concerns about interference with sensitive radio astronomy frequencies between 148.5 and 252 GHz.
• NRAO's filing to the FCC highlights that these frequency bands are widely used globally for radio astronomy to observe phenomena like protostars, protoplanetary disks, and comets, and are also important for satellite remote sensing related to climate and weather.
• SpaceX plans a massive Gen 3 constellation of up to 100,000 satellites operating in W- and D-band frequencies (92 to 275 GHz) to deliver multi-gigabit speeds, which raises concerns about continuous interference as satellites pass overhead.
• NASA has raised additional concerns about the low orbital altitude (as low as 323 km) of Gen 3 satellites, warning of potential conflicts with NASA missions and increased congestion in low-Earth orbit affecting future exploration launches, though it has not formally opposed the application.
• SpaceX maintains that the affected frequency bands are lightly used and has committed to ongoing coordination with radio astronomy stakeholders to prevent harmful interference, while NASA emphasizes the need for transparency and technical rigor to ensure space safety and sustainability.