Hackaday is making a lot about some ARPA funding in the early days, something I’d never heard of. wikipedia mentions it, but my interpretation is that ARPA wanted some tests done about the ionosphere, so the money was there. Not some cold war defense plan that Hackaday is reading into it.
But it might mean the money came from the defense budget, and what remained was something useful for radio and radar astronomy. If you skew it that way, it never had to have a long life, so what we got was gravy.
But I don’t know how march of tye initial cost ARPA paid. In almost fifty years of knowing about Arecibo, I’d never heard of it as anything but a radio telescope.
