On a remote island, these GPS hackers are preparing for an invisible war

Energy grids, data networks, stock markets: how easy is it to shut down our modern world by attacking the systems that synchronise time and space? Meet the jammers finding out.

Harald Hauglin is a toweringly tall man with a salt and pepper beard, wire-framed glasses, and an impish grin. When I met him in September 2024, the pocket of his mandatory hi-vis vest displayed a patch showing a white rabbit on the run with a clock. 

Hauglin is chief engineer of time and frequency metrology at the Norwegian Metrology Service. He is also a "Nerd of the Northern Lights" – a nickname adopted by attendees at the 2024 Jammertest.

Hosted annually by the Norwegian authorities, Jammertest is an open-air hacking festival set on a remote island 300km (186 miles) north of the Arctic Circle. Its aim is simple but mind-bending: to use satellite signals to mess with time itself – and see if receivers in everything from clocks to drones can withstand the pressure.

At the heart of this experiment is a technology that runs much of our modern digital world: Global Navigation Satellite Systems (GNSS).

We tend to think of satellite networks such as GPS as tools for navigation. Yet they also do something else just as important: they transmit ultra-accurate time. Power grids, telecommunications networks, stock markets, transit services and more all depend on the synchronisation provided by GNSS. 

But the importance of GNSS to infrastructure also creates an Achilles' heel. Satellite transmissions are weak, and can be overwhelmed or hijacked by stronger, nefarious signals.

Since Russia's full-scale invasion of Ukraine, such interference has risen dramatically. The most obvious impacts have been on aviation. In May of this year, an RAF plane experienced GPS jamming near the Russian border, while in September 2025, the Swedish Transport Agency said that interference was a daily occurrence. 

Norway's government is now one of several preparing for a world in which GNSS could become a strategic vulnerability.

So, is it possible to prepare for an attack on our sense of time and place itself? Each year, dozens of engineers, physicists and officials head to the Arctic Circle to find out.

The setting for Jammertest is the village of Bleik on Andøya, a tiny, remote island often used to study the Aurora Borealis. The picturesque venue resembles an engineering summer camp, the epic Arctic scenery and daily waffle buffet all part of the appeal. Yet its purpose is deadly serious.

Jammertest was only in its third official year when I visited, but the idea of testing commercial GNSS receivers to see how they react under intense, if artificial, interference is not new. 

For years, the US military has been running tests to show how receivers react when GNSS is manipulated, held at the White Sands Missile Range in New Mexico. These tests are tightly controlled, however, including what data can be shared after the fact. 

The Norwegians take a different approach, modelling the test event on the white-hat hackathons beloved in the tech industry, where hackers probe for chinks in cybersecurity armour to make software better. Crucially, these tests are done openly, in full view of any visitors to Andøya, and attendees share the results of their tests with other government and commercial attendees on the final night of the event. 

Over the several days I attended the 2024 Jammertest, I sat next to Hauglin in the log cabin-style Bleik Community House, trying not to spill coffee on expensive electronic equipment as he and his colleagues unleashed staged attacks. The job involved feeding false information to receivers in everything from planes to cars to industrial equipment: about where they were located, and often, at what time.

Think of it like this. If you are reading this story in London in September 2026, GNSS manipulation would feed you false information that, for example, you're in Lima, Peru – and it's September 2017.

There are two main kinds of GNSS interference. The first is jamming, or overwhelming signals so that the service is no longer available. The second is spoofing – a hijacking of the radio waves, where a false location and time is offered to a GNSS receiver. 

The most dangerous kinds of GNSS attacks are two-fold. 

The first major risk is extended jamming: a sustained, total wipe-out of GNSS, long enough to run down back-up timing and cause scores of knock-on issues as the digital synchronisation stitching together our modern world begins to fray.

How long a power grid – or any modern digital system – can remain synchronised without access to GNSS comes down to how much money a government or company is willing to spend installing the physical stuff that GNSS otherwise makes irrelevant. Largely, this is a combination of land-based clocks and fibre optic cables to transfer time with extreme precision.

The second, even worse scenario, is a slow-burn, sophisticated spoofing attack that isn't noticed or contained, and therefore never allows back-up systems to kick in. This is essentially a timing-based sneak attack that could dislodge digital systems in one fell swoop.

Both these kinds of attacks go after GPS time, and both involve the most sophisticated and powerful levels of manipulation or disruption – comparable to elaborate cybersecurity attacks. 

They are also the kind of attacks that Hauglin and the Metrology Service, alongside numerous companies who provide industrial time as a service, meet on Andøya to test out.

The aim is to explore how vast digital systems may cope in the short-term following an attack, multiple people told me. For example, by establishing exactly how long the energy grids and mobile networks have before things start to go seriously wrong.

On the first afternoon at the 2024 Jammerfest, there were two test-flights: a Norwegian rescue helicopter, and a small plane, flown by a pilot from Eurocontrol, the European aviation safety body. 

I watched as manipulation of the GNSS signals fed false information to the receivers on both flights, creating location tracks that didn't reflect where the pilots had actually flown. 

The helicopter's location on the flight tracker appeared to move in countless overlapping, panicked swirls, like an anxious doodle on a page – manoeuvres a helicopter wouldn't, and couldn't, pull off in real life. Later, the tracker showed Eurocontrol's test plane making a series of odd, paperclip like patterns in the sky, full of extreme, gut-churning turns. In reality, the plane had been doing wide, graceful loops above the town. 

On the second morning, I watched as Hauglin undertook more sophisticated disruption. Over 40 minutes, he and his colleagues gradually raised the power of the spoofing equipment, strengthening the decoy signal: the electromagnetic equivalent of slowly overwhelming a system before it realises anything is wrong. Like boiling a frog.

As the transmission from the sneaky antenna ramped up, a screen on a monitor mounted on the wall above us showed the area on Google Maps. Steadily, a beacon marking our location moved, misleadingly, out into the Norwegian Sea. 

The impact on clocks was harder to see without complex equipment. To track the "drift" caused by interference – the way a GNSS-synchronised clock can be forced to gradually peel away from the real time – it was necessary to compare GPS time to an uninterrupted reference time. This reference time came via fibre-optic cables unspooled all the way to a GNSS-receiver on the other side of a mountain, where it was safe from interference.

I watched over Hauglin's shoulder as he showed me a chart that tracked the spoofed clock's drift, measured in nanoseconds, away from the reference time. 

As Hauglin said, the issue is that we tend to take time for granted – and we certainly don't like to think of it as a weapon. 

New options to replace, or strengthen, GNSS are alsobeing proposed or developed all the time. 

Do you remember the white rabbit on Hauglin's shirt? As well as a reference to the character in Lewis Carrol's Alice's Adventures in Wonderland, the motif also represents White Rabbit – a precision timing system developed at Cern in Switzerland, which can deliver time accurately to less than a nanosecond. 

This and other timing systems usually replace the reliance on satellites with fibre optic cables, and atomic reference clocks. And they are much harder to hack.

But nearly everyone I spoke to agrees that there is no single alternative system that can match every service GNSS has come to provide. 

"There is no silver bullet, which is why you need a combination of systems," says Dana Goward, who has campaigned for policies to protect GPS since 2013, as the co-founder of the Resilient Timing and Navigation Foundation. 

In 2024, Goward told me he believed spoofing was only going to get worse – "it's cheap, it's easy" – and that one of the biggest risks could come from the other GNSS systems themselves.

In June 2026, those fears were realised when a group of experts warned that Russian satellites have beamed interference from above, disrupting GPS signals across Europe for brief periods.

In the past, GNSS interference was limited to a region or a border area, as radio signals from Earth can only travel so far. Now, with interference also coming from above, nowhere and nothing will be off-limits.

More like this:

• What a war in space might look like

• The cold war nuke that fried satellites

• The cyber attack that turned back time

Given that so much of the Jammertest event for the Scandinavians was, implicitly, about preparing for the risk of some kind of attack by Russia, I was slightly curious that the 2024 event was being held so openly. The level of security, and the presence of Norwegian intelligence, was discrete.

The openness, however, is also part of its point.

"Is it also to show: 'we are becoming more resilient? We're dealing with this?'" I asked Tomas Levin, the senior engineer for the roads administration, and one of the organisers of Jammertest. 

"Of course," he said. "So come on, Russia, go ahead."

* This article is based on an extract from Katherine Dunn's book, Little Blue Dot: How GPS Shaped the Modern World, published June 2026 in the US and the UK.

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