Scott Tilley, an independent satellite researcher, says about 171 Starshield satellites built by SpaceX for the NRO transmitted in the 2025–2110 MHz band, which is reserved for Earth-to-space uplinks. He detected signals over the U.S., Canada and Mexico, with probable spillover elsewhere. Although no major outages have been widely reported, such transmissions could interfere with ground-station uplinks and critical satellite communications. The cause remains unconfirmed and may prompt regulatory and technical follow-up.
Researcher: 171 SpaceX-Built NRO Satellites Transmitting on Reserved Uplink Frequencies
Independent researcher Scott Tilley reports that roughly 171 Starshield satellites built by SpaceX for the U.S. National Reconnaissance Office (NRO) were transmitting on frequencies reserved for Earth-to-space and space-to-space links. Tilley identified anomalous signals in the 2025–2110 MHz band and traced broadcasts over the United States, Canada and Mexico, with probable spillover into neighboring countries.
The 2025–2110 MHz range is internationally allocated primarily as an uplink band — used by ground stations to send signals to satellites — and is carefully managed to avoid interference with critical space communications. Because satellites and ground stations expect that band to be quiet except for authorized uplinks, unexpected transmissions from a large constellation can disrupt reception and coordination.
“This particular band is allocated by the ITU, the United States, and Canada primarily as an uplink band to spacecraft on orbit — in other words, things in space, so satellite receivers will be listening on these frequencies,” Tilley said. “If you’ve got a loud constellation of signals blasting away on the same frequencies, it has the potential to interfere with the reception of ground station signals being directed at satellites on orbit.”
While there have been no widely reported major service outages linked to these transmissions, the risk is significant: interference in this band can affect ground-station uplinks, telemetry, command channels and other satellite-to-ground operations used by civil and scientific agencies. The band is also used by spacefaring organizations for critical missions, so even intermittent or localized interference can create operational headaches.
Tilley’s findings are based on signal analysis that correlated timing, frequency and location of the transmissions. He says the pattern is consistent with an on-orbit source rather than ground-based transmitters. The underlying cause — whether a configuration error, software issue, or incorrect frequency assignment — has not been publicly confirmed.
Spectrum allocations are regulated internationally by the International Telecommunication Union (ITU) and nationally by agencies such as the Federal Communications Commission (FCC) in the United States. Resolving a large-scale misconfiguration typically involves coordination between the satellite operator, government customers, and regulators; in some cases satellites can be reconfigured remotely, while other fixes may require more involved measures.
What to watch next: further technical analysis, statements from the satellite operator or government customer, and any regulatory inquiries that may follow. Independent monitoring by radio observers like Tilley often helps surface issues that then require formal investigation and remediation.
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