auonsson Profile picture
Apr 28, 2024 10 tweets 3 min read Read on X
Ships in south Baltic Sea are seeing GPS interference. Stated by SE authorities, individual reports and is subtly seen in replays of ship traffic.

While the area has long been affected by GPS-jamming of aircrafts, these are the first confirmed surface effects. Reason unknown. Image
The official reports are from NAVTEX warnings, published last 24h.

SE report state "GPS and AIS interference seen in areas south Öland and south Baltic Sea."

From DK: Bornholm DGPS-transmitter is out of order. Those complement sat-based GPS and heightens accuracy. Not today. Image
The area is one of the worlds most busy shipping lanes.

The reason is so far unknown and might very well be something benign.

The Baltic Jammer in Kaliningrad is hindered by physics to be the cuplrit (unless it is spacebased, which has not been indicated.)
Besides the official reports the Marinetraffic-replay looks odd with jumpy ships. Unfortunately MT is not working as per usual so I cant record it.

There is also this report and a sailor in my DMs confirming.
Thanks to the awesome service at in a few days we will all be able to analyze what the jammed ships of Bornholm actually sent with their AIS-transponders. Here's a preview of one possible analysis method, a visual one. web.ais.dk/aisdata/
There are lots of data fields! I plan on running code that looks for unnatural speeds.
If there is a sudden speed change, and especially if it does not match the log of the ship, something is up. That's one way of finding traces of GPS-interference. Interested? Dig in! Image
Ship after ship reporting "NO GPS" in South Baltic Sea. Right now.

To be very clear: we have no idea why they are losing GPS. This is 24 hours fresh. It is confirmed by SE maritime authorities though.
Sailors in the area, please post data/images/videos/recordings if you encounter the South Baltic GNSS/GPS interference.

DMs are open and I am discreet if need be.

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More from @auonsson

Jan 30
4 days ago Baltic States + UK wrote a letter interpreted as "Baltic Sea closing for shadow fleet".

No sanctioned tanker has arrived since (unusual*) but coming 24-36h the claim will get its first test with 5 sanctioned tankers inbound. Image
* It is unusual to not see daily sanctioned tanker arrive to Baltic Sea, usually a few each day.

But, the last 4 days lull ismight be explained by weather: Atlantic storms, low temperature and an increasingly frozen Gulf of Finland.
The ice is growing thicc around Russia's Baltic oil terminals.

Ice data outlets list a bunch of ice-breakers in service, but other sources have stated Russia lack capacity to keep the ice-sensitive rust-bucket tankers in play. Image
Read 10 tweets
Jan 17
Underappreciated fact:

The paths and positions of the cable damages around New Years 2026 were to most of Estonia's internet backbone routes.

Had it fully succeeded/happened by accident (lol) Estonia would have been left with a crippled connectivity. Image
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Read 5 tweets
Dec 31, 2025
I just deleted a post where I had misread a press release.

5 cables have been damaged, but 3 of those from storm conditions. Image
I might not have been that wrong.

There is a SE-EE incident and a FI-EE incident.

The SE-FI is described as two breaks on the same cable last I read.

As per usual the details, allusions and contexts are vague in news and statements.
Updated map of cable breaks between Sweden and Estonia, based on press release from Estonian ministry for digital affairs.

The details are murky and partly incoherent and I have asked Swedish authorities for clarification.

Whats clear: there are several breaks on one cable. Image
Read 8 tweets
Dec 20, 2025
Russian logistics ship ADLER is at anchor IN Sweden.

Possibly broken down. Usually runs heavy weapons to Russian bases in Africa / Middle East.

Was inspected by military aircraft 2h ago. Swedish Coast Guard just arrived to area.

Tnx @butafly over at the better site. Image
@butafly Coast Guard patrol is about to dock in Höganäs, port a few kms south.

Here they will likely pick up more staff for whatever they plan.

Guess: Nationella Insatsstyrkan or something similar. NI are police, but carry proper guns. Or, a cadre of really nitpicky bureaucrats =) Image
@butafly ADLER is very much IN Sweden, only 2 nautical miles from the coast.

Legally Sweden have much more legroom here then if she was outside our territory.

Let's see if we use it. Onboard one would likely find weapons or supplies headed for Libya/Syria or similar Russian base.
Read 18 tweets
Sep 23, 2025
@pmolpmol lists three ships interesting as suspected drone carriers in last night attack on Copenhagen Airport.

In this thread, I will argue that Russian ship ASTROL 1 is an excellent fit.

Right time, right type, erratic track just before attack, highly suspicious background. Image
Article that led me down this rabbit hole, by @pmolpmol nyheder.tv2.dk/live/krimi/202…
ASTROL 1 is a largely flat cargo ship with hatches that likely would serve well as drone pads.

She is a similar model to SCANLARK, recently apprehended by German authorities on drone suspicions and to PORT OLYA 4, drone import ship on Iran trade. Sunk by Ukraine. Image
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Read 15 tweets
Sep 22, 2025
Copenhagen Airport is closed for operations because of drones in the air.

Northern Europes most busy airport. Image
Plane diverting last minute. Image
Copenhagen Police in a ”massive operation on scene” (commanding police officer to news)

dr.dk/nyheder/indlan…
Read 21 tweets

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