Quite the shocking disaster when it can be seen from space/orbit. :(
There is no hoping everyone is "ok"; they aren't.
I just hope things get better for them real soon, and that no more lives are lost there.
Limited communication is being restored in Tonga through satellite, high-frequency radio and motorboat after a violent underwater volcano severed a fiber-optic cable connecting the remote island to the world. The Hunga Tonga-Hunga Ha'apai underwater eruption – equivalent to a 10 megaton blast, it's estimated – on Saturday …
This is an interesting read:
So, they grapnel one of the broken ends up, off the seabed (that could be somewhere between 1km and 7.6km below the surface).
I guess they have to move the ship "backwards" (along the line of the cable), as there is unlikely to be any slack in the cable to allow it to be raised straight up that far !
The cable end is brought onto the repair ship and they test/check if the fault is there. Then they attach a buoy to it, and set it to sit on the surface, awaiting for it to be spliced onto the other end eventually.
Then they move off and find the other end and do the same.
So, once the two ends have been checked/repaired, those two ends could be maybe a few km apart (where before they were "joined" to each other).
I would imagine they then have to splice in a new long section of cable to take account of this increased distance between the two ends..and once spliced, they then drop the cable back onto the seabed...but they'll be a long "run" of cable that is now looping around on the seabed...but at least the connection will be working.
And it's more complicated than just dropping the cable off the back of the boat. Depending on how close the original path was to the volcano, the sea bed may have changed and they'll have to survey it again, and pick a path for the cable to take. If it's in shallower waters it might have to be buried, so they'll use a trenching tool dragged behind the ship to cut a trench, place the cable in it, and refill over the top.
Still, the people doing this sort of thing know their job, and they've dealt with this sort of problem before.
It's been covered here before in the Geek's Guide, but a great place to learn about this kind of stuff (and indeed the history of communications generally) is the Museum of Global Communications in Porthcurno in Cornwall.
Spent a very enjoyable day there a few years back, including a short stroll down to the nearby coast to the actual point where the transatlantic cables used to come ashore.
Adding to that the Goonhilly station also reasonably close by, it's a very rewarding place for a short visit (or a longer one, Cornwall is lovely).
The CS Reliance is usually found fixing one of the cables in the highly congested areas of the Malaysia/Indonesia/Singapore waters. They are pretty much the best team for the job.
Can't help but suggest that a bit more resilience for Tonga is needed (in terms of subsea cables) linking it to Nuie and landing the non-Fiji leg of Southern Cross there too would have been a good plan or linking the far end of the domestic extension to American Samoa...
"All we need is to activate that service and perform that contract. We are now awaiting instructions. We have one simple message for the Government of Tonga. We can help. Please get in touch."
Surely Mr Musk can step in here...?
Just get him to send in some StarLink sat dishes by parachute and then they can connect these to the end points of the various local ISPs....a bit of local network techs "wizzadry" and a few network cables will do the trick, even if only on a temporary basis, until the undersea cable is fixed.
The "marketing" benefit to Musk of re-connecting Tonga to the web must easily outweigh the cost of some satellite dishes and dropping them in 'chute?
...but I suggest that the surviving population of Tonga has more to think about than chasing parachute drops and undertaking wizard bodge jobs with satellite dishes. They have no clean water, buildings will be unstable or collapsed due to the weight of ash on their roofs, crops have been totally destroyed, and many other things that we can guess at but don't know for sure. A shortwave radio to communicate with NZ or with Fiji will do for now.
Mr Musk tried to do the TechBro Steps In thing with the rescue of the boys in that cave in Thailand, and that didn't go well.
> no clean water, buildings will be unstable or collapsed due to the weight of ash on their roofs, crops have been totally destroyed
But that's nothing compared to not being able to update your status on Facebook, isn't it! Hell, it didn't happen if you can't tweet about it or post pictures of your rations.
Money. What else? (see this article
TLDR: After a previous incident where the fiber cable got cut an agreement was signed between Kacific and Tonga Satellite Limited (as far as I can tell a government owned company) to provide satellite bandwidth for a lump sum payment of roughly 6 million USD up front. Apparently someone in the government balked at that amount of money (probably because when the undersea fiber cables are working they don't need it) and the Tongan government has since been frustrating things and delaying on making the payment.To the point of trying things like saying TSL wasn't authorized to sign the contract and de-registering it, which has since been ruled illegal by the Tongan supreme court
I'm getting the impression some of the Tsunami were 15m high. I'm not sure the hams will have functional equipment and if they do power is another problem. These things need to be more substantial than something in what is essentially a garden shed when it comes to waves - no offence intended to the Tongans, their homes are normally more than adequate. But we need things that are dug into bedrock and can be used in a minimum way by anyone who knows where they are for situations like this.
"Hams" are a resourceful lot.
Rigging a new HF antenna isn't particularly difficult if there are suitable buildings/trees in existence.
Most modern lightweight HF sets are 12v powered and a vehicle with a running engine will allow emergency comms.
I'm sure that Tongan Radio Amateurs are well practiced in emergency planning
Maybe to have some hams (radio amateurs) there - they know how to communicate world wide, you can't always trust the commercial companies with profits in their minds! Yes, hams are limited by kind of stupid rules so they wouldn't compete with these big companies, but maybe in cases like this...?
There was a story before the AT&T breakup when a young employee researched how much AT&T was losing to amateur phone patches and sent it up the management chain. He got a call from a top executive to see him in his office. So bright young employee gathered all of his evidence and went to the executive. The top-level executive informed the bright young thing that people in Antarctica used phone patches to communicate, many other people were well served by the radio amateurs etc. and, by the way, I'm a ham. Go away and never let me here of this again.
This is third/fourth hand but I believe that it was true.
The cable was probably about as good as they could do. Its prohibitively expensive to safely bury a cable in regions like this (have a look on google earth) and the wavelength of tsunami can be hundreds of KM so any cable can be pulled from the sand and dragged until it snaps.
"Let's focus on airdropping things like food and water, and supplies to build or repair shelter. Let's not take capacity away for a PR stunt."
Of course...but this story was simply about the break in the 2 cables...and how to fix it.
And for sure, there is a desperate need for emergency water supplies and no doubt many other things - but all of that is obvious and doesn't really need to be stated.
After all, it's not as if emergency services don't know what a tsunami is and the devastation it can cause.
> Tonga is on the 30,500km Southern Cross Cable Network fiber optic cable that links US West Coast, Hawaii, New Zealand, and Sydney. The breakage is on the line linking Tonga on the network to Fiji.
Yes and No.
No : Tonga is not on the Southern Cross Cable, nor on the Southern Cross NEXT cable.
Yes : the broken cable is the line linking Tonga to the Fiji... But that cable is called Tonga Cable ( https://www.tongacable.net/ )
The second broken cable is the Tonga Domestic Cable Extension. As the name sais : it's a domestic cable for the communications between the various Tongan islands.
If Southern Cross ( or the Southern Cross Next ) had been broken the impact would have been much more important.