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SKA Telescope To Offer Neighbors Cheap Broadband
An anonymous reader writes The Square Kilometer Array is a giant telescope currently being built in the middle of the Karoo in South Africa, which when complete will be 50 times more sensitive than any existing Earth-based telescope. The problem is that it's so sensitive, the thousands of antennas need to be protected from terrestrial radio interference. Given that cell masts and technologies like TB white spaces are the only way people living in the remote areas near SKA are going to be able to get affordable net access, this is a bit of a problem. In order that its neighbors aren't completely cut-off, SKA is offering them subsidized satellite broadband instead. Which is nice.
Seriously, I understand that they're avoiding the much stronger radio signals from terrestrial cellular networks, but the article definitely explains it poorly.
Since the SKA requires staggering amounts of bandwidth between components of its antenna array, I expect that once it's been installed they'll switch to piggybacking off those fibres. But this is a stopgap to preserve radio quiet while the system is built.
Sounds like a decent solution, we have a similar issue with our space telescopes in the US, so we have a radio quiet zone to deal with it. However, the residents are simply required to make do without WiFi, cellular broadband, etc.
http://en.wikipedia.org/wiki/U...
-- You are in a maze of little, twisty passages, all different... --
i like the idea, but the problem with fiber being cheep and not worth anything at scrap, criminals are not the brightest bunch out there. they dig it up assuming its copper and when its not, its still damaged
have you seen my sig? there are many others like it but none that are the same
So, you've checked that the COTS WIFI equipment isn't going to radiate harmonics in any of the frequencies scanned by the radio telescope(s)?
What exactly makes this a "space" telescope?
Presumably the fact that it is peering into space and not your neighbour's bedroom window or ships on the horizon.
Even damaged fiber can be fixed though. And as far a deep, I'm thinking 20'+ down. Make it cost more than copper prices to attempt to get at it.
So you're going to make it cheaper by digging a 20' trench into bumfuck nowhere?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The area is extremely empty in the first place. That's why they chose it for (part of) the SKA.
The antennae will have dedicated fibre connections (the bandwidth needed for the aperture synthesis is, um, scary, but I suspect
running fibre or copper from there to every village and isolated farm would be stupidly expensive. Carefully chose satellite equipment will broadcast very
little outside it's beam, and on quite specific wavebands.
The article admits that it's not perfect (latency, download caps) but it's better than nothing and imposing radio quiet was an absolute condition of South Africa getting part of this very high prestige project.
I am aware that resources theft has been a problem in poor areas, where recyclables like copper are routinely stolen, but still, wouldn't it have been cheaper, in the long-term, to trench DEEP, build monitored deep equipment vaults with sensors back to the security office of the telescope for access monitoring, and do fiber backbone to the neighborhoods, handing off to either some radio frequency that's not a problem or using copper or fiber for the last mile? Once the infrastructure is in, assuming it's done right, it should be fairly low-maintenance and difficult to steal, and if the only copper is either the last-mile or within the residence like a FIOS or google-fiber solution then there's much less actually worth stealing.
Actual single-mode fiber cable isn't very expensive when new and really isn't worth much when used, so attempting to scrap it out wouldn't be worthwhile.
The array covers over 3000km. I doubt trenching fiber to every resident in that area would be cheap at all.
Why stop at the moon? You could put half the array at Neptune's leading Trojan and the other half the the trailing one and synthesise a REALLY big aperture.
Seriously, the answer is cost. It's expensive enough building this many super-high-quality dishes and associated support structures and installing and operating them in empty (almost) deserts in Australia and South Africa, plus the 50 thousand kilometers of optical fibre to link them up and the multi million core supercomputer to do the aperture synthesis.
Putting all of that on the moon would cost trillions and take decades. The signal would be cleaner (except that you are outside the Van Allen belts so you have to worry about solar radiation) but the signal on Earth is good enough to do the science. Also the moon is actually too small. Even if you spread the dishes over the whole far side you couldn't get as big an aperture as they get with part of the array in Australia and part in Africa.
What they're going to get is years of work associated with the building and more years, but of less work associated with the operation, plus probably things like roads.
The telescope when finished (2025) will need more total bandwidth between its antennae than the entire remainder of the internet is projected to need at that time.
It will be dedicated fibre, about 50 000 km of it.
What we're talking about here is connecting the (very few) isolated farms and villages within one or two hundred miles of an antenna. With a population that
distributed it isn't a last mile issue it's a last hundred miles issue.
It's not a line. It's roughly a spiral. See https://www.skatelescope.org/l.... 3000 sqkm is probably the area of the radio-quiet park. But it's population, apart from the astronomers and engineers is tiny
Also the moon is actually too small. Even if you spread the dishes over the whole far side you couldn't get as big an aperture as they get with part of the array in Australia and part in Africa.
Not that I'm defending the "The SKA is stupid, we should build it on the moon" point-of-view, but for the record, the SKA isn't going to do aperture synthesis between the Australian and African arrays. The bi-continental location of the telescope(s) is largely a politically-driven decision.
Putting all of that on the moon would cost trillions and take decades.
We have trillions to bomb people with, but not for science. Unless it leads to better bombs.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
That's an astronomical telescope. A space telescope is Hubbel and the like, up in, you know, space. See also space observatory.
Got them moderator blues I blieve I walk out the do', With these mod-points I been gettin', I 'most never post no mo'