A covert constellation of military satellites built by SpaceX for the United States government has quietly grown into a fleet large enough to reshape how Washington sees and senses the world from orbit. Now, an accidental discovery by an independent researcher has exposed that many of those spacecraft are transmitting powerful radio signals in an unexpected way, raising fresh questions about interference, oversight, and the risks of outsourcing critical intelligence hardware to a commercial giant. At the center of the story is a cluster of classified Starshield platforms whose unusual radio behavior is rippling through the scientific and policy communities.
How an amateur sleuth unmasked a secret network
The existence and behavior of this hidden fleet did not emerge from a government disclosure or a corporate filing, but from the patient work of a single observer listening to the sky. Scott Tilley, an engineering technologist and amateur radio astronomer in British Columbia, was scanning for signals when he picked up transmissions that did not match any known commercial or scientific satellite. By tracking their orbits and signal patterns over time, he linked them to a series of classified payloads built by SpaceX for United States intelligence customers, a finding later detailed in reporting on US spy satellites that had not been publicly acknowledged.
What made Tilley’s work stand out was not only that he identified the spacecraft, but that he documented how they were talking. In coverage that followed his observations, he was described as an engineering technologist in British Columbia who had detected signals that did not behave like ordinary commercial downlinks, a pattern that pointed to a specialized military role and a deliberate effort to keep the system out of public view. The fact that such a significant intelligence asset was first mapped by an outsider, rather than by official notice, underscores how much of modern national security infrastructure now depends on private launch and satellite operators whose activities can still be reverse engineered from the ground.
The Starshield fleet and its unusual radio footprint
As Tilley and other analysts pieced together the puzzle, a clearer picture of the constellation’s scale began to emerge. A researcher found that 170 Starshield spy satellites are transmitting in a frequency band that is normally reserved for Earth-to-space communication, a band typically used for uplink commands sent from the ground to satellites in orbit. Instead of behaving like conventional downlinks that beam data from orbit to receivers on the surface, these spacecraft appear to be sending powerful signals outward, away from Earth, in a way that surprised outside experts who reviewed the data.
That pattern is not a minor technical quirk. In the reporting that followed, analysts noted that the Starshield satellites were operating in a slice of spectrum that regulators usually treat as a protected channel for ground stations, a design meant to keep satellites from disrupting each other and to preserve the integrity of command links. By transmitting in that band from orbit, the classified fleet is effectively inverting the usual direction of traffic, a choice that may reflect a sophisticated intelligence mission but that also raises the risk of interference with other space systems that rely on the same frequencies for critical control functions.
Signals in the “wrong” direction and what they might mean
The most striking technical detail in the public reporting is that the satellites’ radio energy appears to be flowing the opposite way from what engineers would expect. In a detailed account of the discovery, Tilley was quoted as saying that the spacecraft were sending signals in the “wrong direction,” a phrase that captured how the transmissions seemed to be aimed away from Earth rather than toward ground receivers. That assessment, highlighted in a focused segment on Scott Tilley and his measurements, suggested that the constellation might be designed to illuminate other satellites or distant targets in space rather than to serve as a traditional communications relay.
From a strategic perspective, that kind of outward-facing transmission could support missions such as tracking foreign spacecraft, mapping debris, or feeding data into classified surveillance networks that span multiple orbits. Yet the same behavior also complicates the already crowded radio environment in low Earth orbit, where commercial broadband constellations, weather satellites, and scientific instruments all depend on carefully coordinated spectrum use. By operating in a band that regulators associate with uplink traffic, and by sending energy away from Earth, the Starshield fleet is effectively writing its own rules in a part of the spectrum that other operators assumed would remain predictable.
Conflicting counts and a growing constellation
Even the basic question of how many satellites are involved illustrates how fluid and opaque the program has become. One analysis tied the unusual transmissions to a group of 171 SpaceX-built Star platforms, a figure that slightly exceeds the 170 Starshield spy satellites identified in other reporting and hints at a constellation that is still expanding. The discrepancy between 170 and 171 spacecraft is not just a rounding error, it is a reminder that outside observers are reconstructing a classified architecture from launch manifests, orbital tracking, and signal analysis rather than from an official roster.
For policymakers and rival space powers, that ambiguity complicates any effort to assess the true reach of the system. If the fleet already numbers at least 170 satellites and may have reached 171, then it rivals or exceeds the size of many national civil constellations, yet it operates under a veil of secrecy that leaves regulators and international partners guessing about its full capabilities. The lack of a clear public count also makes it harder for scientists and commercial operators to model potential interference, since even a handful of additional transmitters in a sensitive band can change the risk calculus for nearby missions.
Astronomers’ interference fears and the mystery of the uplink band
For the scientific community, the most immediate concern is not the intelligence mission itself but the impact of the satellites’ radio behavior on observations of the universe. An astronomer who was monitoring the sky for other purposes accidentally discovered that secretive SpaceX satellites operated by the United States government are shooting disruptive radio signals into space, a finding that was detailed in a report dated Nov 17, 2025 that described how those emissions could contaminate sensitive measurements. The same account noted that the spacecraft are tied to multiple branches of the U.S. government, a sign that the constellation is woven into a broad national security apparatus rather than serving a single agency, and that its radio footprint extends well beyond what astronomers had anticipated from commercial systems.
Technical experts quoted in that Nov 17, 2025 coverage stressed that it is unclear why the satellites are using uplink signals instead of standard downlink frequencies, a choice that runs against the grain of how most Earth observation and communications missions are designed. In a follow up that drew on Tilley’s data, one report explained that the spacecraft were transmitting in a band normally reserved for Earth-to-space commands and noted that, so far, there have been no confirmed cases of harmful interference with other satellites. Yet the same piece, which highlighted the line “But it is unclear why” they are operating this way, underscored that the lack of reported incidents does not eliminate the risk, especially as the fleet grows and as more scientific instruments push deeper into the same frequencies.
Regulatory blind spots and the role of private contractors
The revelations about the Starshield constellation also expose a gap between how regulators oversee commercial satellites and how they treat classified national security missions. In the civilian realm, operators seeking to use nonstandard frequencies or high power levels must typically navigate a public licensing process that invites comment from other stakeholders and from international partners. By contrast, the covert fleet of US government satellites built by SpaceX appears to have been deployed with minimal public documentation of its spectrum use, leaving outside experts to infer its behavior from signal traces and orbital data rather than from filings that spell out its parameters.
That asymmetry is particularly striking because the hardware itself is built and launched by a private company that also runs one of the world’s largest commercial broadband constellations. When the same manufacturer fields both consumer internet satellites and classified Starshield platforms, any regulatory carve outs granted for national security purposes can blur into the commercial domain, especially if the underlying technologies share components or orbits. The current situation, in which a covert intelligence network can transmit in a band reserved for Earth-to-space communication without a clear public record of how it will avoid interference, highlights how much trust regulators have placed in private contractors to self-manage the boundaries between their commercial and military roles.
Strategic stakes in low Earth orbit
Behind the technical debate over frequency bands and signal direction lies a larger strategic shift in how the United States projects power in space. A fleet of at least 170 Starshield spy satellites, possibly extending to 171 Star platforms, gives Washington a dense mesh of sensors and relays that can watch, listen, and communicate across low Earth orbit with unprecedented persistence. By transmitting in unconventional ways and by pointing energy away from Earth, the constellation may be designed to interact directly with other spacecraft, to map orbital traffic, or to feed data into classified networks that span multiple layers of the space environment, capabilities that would be difficult to match with a handful of traditional, bus-sized reconnaissance satellites.
At the same time, the discovery that an amateur in British Columbia could unmask the system’s radio behavior underscores how fragile secrecy has become in an era of cheap receivers and open-source tracking tools. The fact that Scott Tilley, working outside any official program, could document signals in the “wrong direction” and tie them to a covert US fleet suggests that future military space projects will have to assume that their basic outlines will be visible to the global community, even if their payloads remain classified. For allies, rivals, and regulators alike, the Starshield case is a preview of a world in which national security satellites are both omnipresent and, thanks to independent observers, increasingly hard to hide.
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