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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.
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.