Starlink is unceremoniously shutting down a GPS-style feature that most of the Internet satellite provider’s customers probably never realized existed. But that won’t stop broader momentum toward harnessing Starlink’s satellite constellation as a navigation alternative—especially when GPS jamming and spoofing have become more widespread.

The Starlink satellite constellation owned by SpaceX is designed to provide communications services first and foremost, rather than pinpointing users’ locations like GPS and other global navigation satellite systems (GNSS). However, SpaceX publicly acknowledged in a May 2025 letter to the US Federal Communications Commission that Starlink could deliver positioning, navigation, and timing (PNT) services. A handful of savvy Starlink customers had even been accessing Starlink PNT capability for several years until Starlink recently decided to shut down access, according to PCMag.

“The beauty of Starlink as a backup to GNSS is that it’s such a different system—frequencies 10 times higher, bandwidths 10 to 100 times wider, power 100 to 1,000 times stronger, satellites 100 times more proliferated,” said Todd Humphreys, director of the Wireless Networking and Communications Group (WNCG) and the Radionavigation Laboratory at The University of Texas at Austin, in correspondence with Ars.

The built-in location feature was previously accessible through the Starlink mobile app’s Debug Data section. It enabled users to give local networks access to their Starlink dish’s “precise latitude, longitude, and altitude with no authentication required,” according to Paul Sutherland, a software developer, in a blog post.

Starlink dishes have their own GPS receivers to help pinpoint their own locations so they can find the nearest Starlink satellites. But the user location feature also offered an option to “use Starlink positioning exclusively.” Humphreys has described that Starlink PNT capability as a “cheat code for those who knew about it,” because it even worked in regions with GPS interference.

That has proven especially useful for users who installed the latest Starlink dishes on recreational vehicles and boats. In one case study highlighted by PCMag, a sailboat cruising through the Red Sea with the Starlink Mini dish—a user device released in 2024—was able to exclusively rely on Starlink positioning data despite GPS jamming and spoofing.

But on April 21, Starlink users received email notifications telling them that dish location data would no longer be available as of May 20, 2026. There was no specific rationale given for the decision, and SpaceX did not respond to an Ars request for comment.

Why Starlink works when GPS doesn’t

Starlink has drawn increased attention as a navigation alternative at a time when GPS jamming and spoofing have become widespread worldwide, impacting shipping routes from Europe to Asia and disrupting hundreds of flights on a daily basis. Jamming involves broadcasting strong signals to overpower the relatively weak radio signals coming from GPS and other global navigation satellite systems. Spoofing relies on transmitting false signals that mimic authentic satellite signals to trick signal receivers into calculating erroneous positions for aircraft and other users.

Global navigation satellite systems such as GPS are vulnerable to jamming because they transmit relatively weaker signals from higher orbital altitudes farther away from Earth. But Starlink and other low-Earth orbit communication constellations transmit higher-power signals in the Ku-band with wider bandwidths that are difficult for adversaries to disrupt through jamming.

Starlink is also much more resilient to spoofing because its user dishes are phased array antennas capable of focusing in the direction of a fast-moving Starlink satellite to detect its specific signal. Starlink’s PNT capability relies on round-trip time measurements between the user dish and a single satellite at a time, Humphreys said. The two-way communication between the user dish and satellite also relies on encrypted signals and can incorporate user authentication features.

By comparison, civilian GPS receivers mostly use omnidirectional antennas that passively receive unencrypted signals from many different points in the sky—they calculate a user’s position by receiving one-way “pseudorange” measurements from many satellites at once to ensure maximum accuracy. That makes them much more susceptible to false signals from adversarial spoofing.

But Starlink PNT’s accuracy is still limited compared with standard GPS. Humphreys and his colleagues have demonstrated how a mock Starlink service can produce navigation and timing solutions with 10-meter-level accuracy if Starlink supplies the real-time clock and orbit corrections—albeit only after a minutes-long processing delay. “We’re now refining our techniques so it can be done in tens of seconds rather than tens of minutes,” Humphreys told Ars.

One challenge is that Starlink’s round-trip time measurements are currently less accurate than the pseudorange technique used by dedicated global navigation satellite systems, Humphreys said. That is in part because Starlink satellites have less precise timekeeping capabilities compared to dedicated GNSS satellites equipped with atomic clocks.

The fact that Starlink PNT is limited to communication with a single satellite at a time also constrains performance, whereas receiving multiple satellite measurement signals from many different angles could improve its accuracy. That goes back to how Starlink user dishes can only form a beam to a single satellite at any given time, Humphreys said.

Despite the current performance constraints, Starlink customers who used the location data feature have expressed dismay at losing it. But SpaceX may have decided to block access because it didn’t want to deal with the liability of giving users access to a location service with “decent but variable” accuracy, Humphreys said.

Other possibilities include wanting to prevent “bad actors” from using the Starlink PNTT capability, or SpaceX potentially cutting off free access to pave the way for Starlink PNT’s for-pay debut, he suggested. The timing of SpaceX’s decision coincides with the company’s preparations to go public with an IPO as soon as this summer.

Finding the third way

Regardless of what SpaceX chooses to do, researchers have already demonstrated how to independently harness signals from Starlink and other low-Earth orbit communications satellite constellations.

In 2021, a team led by Zak Kassas, director of the Autonomous Systems Perception, Intelligence, and Navigation (ASPIN) Laboratory at The Ohio State University, showed how electronically eavesdropping on signals from six Starlink satellites could pinpoint locations on Earth to within 8 meters of accuracy—although that required 13 minutes of tracking rather than delivering instantaneous results.

Such opportunistic eavesdropping is challenging, because Starlink is consistently optimizing for its primary satellite Internet service by turning beams on and off, or sometimes switching beams as the fast-moving satellites talk to many different users, Kassas explained. That creates unpredictable jumps in the signal timing estimates that the researchers rely upon to calculate positioning data.

To tackle those challenges, Kassas and his colleagues use Doppler measurements of signal frequency changes that reflect satellite motions relative to the receiver, along with software algorithms to correct for timing errors. They have also deployed phased-array antennas—capable of communicating with just one or two satellites at a time—in combination with low-gain, omnidirectional antennas that can capture signals from nearly 10 satellites at a time. By 2025, the researchers had shown how to harness signals from an average of three Starlink satellites to deliver positioning results to within 2 meters of accuracy in just 20 seconds.

But this general eavesdropping strategy is not just limited to Starlink’s thousands of satellites—they have also exploited satellite signals from Orbcomm, Iridium, Starlink, OneWeb, NOAA, and the dedicated PNT constellation, Xona. “I’m not really married to Starlink—I love them all,” Kassas said.

The team has demonstrated this alternative navigation solution with ground vehicles, a high-altitude balloon, and a drone. One of the latest experiments showed how exploiting signals from both Starlink and OneWeb satellites could improve ship navigation accuracy off the west coast of Greenland in the Arctic, meaning that the technique could probably work nearly anywhere on Earth.

All this suggests that people may not have to wait much longer for new GPS alternatives, whether they come directly from Starlink or third parties. Kassas and his team have already licensed their technology to some organizations. “I think people are hungry and hurting in the absence of GPS or GNSS, and they want these solutions,” Kassas told Ars.