this post was submitted on 26 Dec 2024
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NATO is ready to help Finland and Estonia as Finnish authorities probe an oil tanker that sailed from a Russian port over the possible "sabotage" of a power cable linking the two member countries, alliance chief Mark Rutte has said.

"Spoke with (Estonian Prime Minister) Kristen Michal about reported possible sabotage of Baltic Sea cables. NATO stands in solidarity with Allies and condemns any attacks on critical infrastructure.

"We are following investigations by Estonia and Finland, and we stand ready to provide further support," Mr Rutte said on X.

Earlier, Finnish authorities said they were investigating an oil tanker that sailed from a Russian port for the "sabotage" of a power cable linking Finland and Estonia that was damaged the previous day.

The Cook Islands-registered ship, named by authorities as the Eagle S, was boarded by a Finnish coast guard crew which took command in the Baltic Sea and sailed the vessel to Finnish waters, a coast guard official told a press conference.

"From our side we are investigating grave sabotage," Robin Lardot, Director of the Finnish National Bureau of Investigation, said.

"According to our understanding an anchor of the vessel that is under investigation has caused the damage," he added.

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[–] [email protected] 4 points 1 day ago (1 children)

Has to be an extra 70+ meters higher than that because as your math shows, the straight line will intersect the curvature of the earth meaning any container ship passing would block the signal.

[–] [email protected] 3 points 1 day ago* (last edited 1 day ago) (1 children)

Huh?

It shows that if h0 is 380 meters then a building 130 km away would be below the curvature if its less than 286.44 meters tall, thus not visible, but any portion of a building taller than that would be visible.

So two 380 meter buildings 130 km away is visible to each other (at least the portion above 286.44 meters).

The 69 kilometers is the distance to horizon... nothing to do with the buildings heights...

Am I not understanding this correctly?

Edit: about this:

any container ship passing would block the signal.

Yea the top of the building would be above the horizon by almost 100 meters, definitely visible

[–] [email protected] 3 points 1 day ago (1 children)

What is the height of the laser beam above the horizon at distance d1?

The picture and the calculator implies it is 0.

Now imagine something with non zero height is sitting at the curvature midpoint at distance d1. Container ships are 70+ meters high.

[–] [email protected] 3 points 1 day ago

If one building is 380 meter, but the other one at 130 km away is 286.4434 meters tall, yes it would be zero. But my (hypothetical) proposal would say both buildings are 380 meters, so there would be a 93 meter clearance for ships to pass below without interrupting the lasers.