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Broadband To Hit The South Pole
Albanach writes: "According to this story from the BBC bids are being invited to lay a fibre-optic cable some 1600 kilometres over polar ice, linking researchers at the South Pole with the rest of the planet. Currently, researcher's communications rely upon older satellites that have drifted from their geostationary orbits into ones that are now at least partly visible from the pole. The new cable will be laid on top of the 4km ice cap, and will have to cope with repeated freezing and stretching as the ice moves."
Iridium is back up and running, covers the entire planet (the satellites are in low polar orbits) and the U.S. Government has a bulk buy deal on Iridium satellite minutes. (DoD now owns part of the system, having bought in after the bankruptcy.)
Instead of laying the cable in a straight line, you lay it in S-shapes. Big S-shapes. That way, there's LOTS of slack, say 500% slack, for the ice sheet movement.
Of course, you have to use a fairly flexible conduit -- copper piping should do nicely, as long as you can figure out how to make sure it doesn't kink too badly on compression. The S-shapes, again, would help, but a better material would be even better. Maybe copper line with a thick kevlar braid, along the lines of the braid used in a Chinese finger puzzle/trap.
The Canadian Armed Forces has to recalibrate their microwave dishes every eight years or so up north for CFS Alert on Elsmere Island, because the ice moves. That gets expensive in the long run (Snowcats, helicopters, men), and would be MUCH worse for Antarctica.
And finally, finding a break in the fiber wouldn't be too hard, ever heard of a time-delay reflectometer?
Do daemons dream of electric sleep()?
Actually, I think going wired is a great test to see if it can be done. If we happen to take this space exploration thing seriously, we are going to need to figure out how to keep cables from breaking in *much* colder regions (dark side of the moon). The research that comes out of this I think will be well spent
Who is John Galt?
One interesting note: I think the ice shifts about 10 meters per year at the pole. Don't know what the rest of Antarctica is like, but it presents an interesting problem if they are planning on laying the cable on the ground...
Last month, Wired ran an article about the new construction at the South Pole. It makes no mention of this fiber.
As an Engineer for one of the Telephone Companies, I can tell you that fiber is stronger than you think. I had a pole get hit, knocking the cables the ground- a few 18 wheelers drove over the cables, partially crushing a copper cable. But, the two fiber cables were uninjured (part of their sheathing was shorn away, though).
Still, running fiber to the South Pole is idiotic- think of how long (and how costly) the FLAG project was!
Lovely solution, just one problem: They don't stay put.
Sure over the equator they can orbit at the same rate the planet rotates and so appear "fixed" but that only works over that narrow ecliptic. Instead to cover extreme N. & S. latitudes one needs sats on a much more inclined orbit and then they're out of sight much of the time, a dozen or so would be required to provide continuous coverage. That means a couple of expensive launches, a serious of expensive sats, and of course their own-going management (course-corrections, problem resolution, etc.)
Why not build a series of microwave repeaters or such, bring the cable to the shore then broadcast the rest of the way? A couple of reasons:
Yes fiber isn't the most robust material on its own. On the other hand it can be clad in all sorts of super-durable materials to protect it.
To protect from stretching the fiber might be coiled inside an outer cladding so it's 2x or 3x as long as required. Or it could be threaded through an outer cladding (think 'garden hose') so it can slide back and forth under slight tension between 1km "reservoir" loops.
Of course there's still the problem of powering the repeaters, but then that's why this contract is out there: To get folks interested in solving the problem.
Hmm, what would the Thunderbirds have done?
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
The theories posed here are interesting. One fact has not been stated:
Things you build on ice or tundra or whatever froze will sink below the ice surface. Re-adjustments because the ice is moving???? Not always.
Look at the houses / buildings built on arctic areas. They are on stilts. That is to they can:
1.) Insulate themselves from the ground. Not to make the inside warmer, but to keep the outside cooler. The heat from someting will cause the ground to melt.
2.) They can jack up the stilts of the building/house after it does sink.
A cable on ice will be, IMHO, thrashed. The ice moves, opens, and closes. Steel cables to protect it? No way. Not strong enough. And then put something heavy ( the copper pipe idea ) on the ice? The pipe will create heat on the ice just by being there. And then it will sink.
This idea needs more thought.
I was in Longyearbyen, Svalbard ( 4 hour flight north of Norway ) last week. I've seen it first hand. They were digging up a cable in the center of town last week because the cable was shifting. Putting this cable down was like building a road. Layers of big rocks, layers of small rocks, then paper, then the cable.
This was in an area of tundra, not ice. The ice would be worse. And 1500 km? I'd hate to be the guy in the service truck on that account.
Bill