a little Information to the last Stand at Arecibo
Sometimes I feel like an ant.
Actually, that syntax implies that I might have a hankering for some chocolate-covered formicidae, but that’s not right. What I mean to say is that sometimes – usually after dinner, it seems – my mind zooms back in hope of seeing the big picture: trying to get the establishing shot’ on life, SETI, and just what the heck we’re doing here in the lush foliage of Puerto Rico. And the first jarring revelation afforded by this wide-angle view is that we’re just ants.
There have been ten thousand generations of Homo sapiens before us. Since it’s a fairly good rule of science to assume that anything you observe is typical (until shown otherwise), there may be ten thousand generations to follow.
But are these thoughts merely wishful thinking, or worse, just hubris? That’s what I wonder when the after-dinner camera pulls wide. It’s traditional to state that SETI began in 1960, with Frank Drake’s clever experiment in West Virginia. Consequently, we see ourselves as the first generation that’s tried to locate extraterrestrials, and figure that he who dares, wins. But of course we’re not the first. Karl Friedrich Gauss, whose name is familiar to anyone who has progressed beyond high school algebra, had plans to signal Moon dwellers 150 years ago. His schemes to gain the aliens’ attention with flashing mirrors or geometric patterns in the forest seem quaint to us now, but Gauss was not dumb (heck, his brain is in a jar at the University of Gottingen!)
so it goes …
The guts of any SETI experiment lie coiled within its digital signal processors. Deep inside these unimposing aluminum boxes, herds of electrons shuttle back and forth at the command of circuitry and software, sorting the incoming cosmic static by frequency, and hunting for the faint, slowly varying tone of distant transmitters.
For more than a decade, Project Phoenix has used digital signal processors originally built for NASA’s SETI search - the one that was halted in 1993. Sure, we’ve improved these devices a great deal, but in the digital world, a hardware design that’s a dozen years old is museum fodder.
The world has turned. The old processor, known to its pals as the Targeted Search System (TSS), is still around, hunkered down in a tractor-trailer container parked outside the observing room. There was so much electronics in this baby that the trailer required 38 kilowatts of full-time air conditioning just to keep the chips cool and calculating. But we use something different now - a new, modular system that is rather straightforwardly called the New Search System (NSS).
The NSS takes up a small fraction of the space of the old signal processor, which means it fits nicely in the Observatory’s computer room, saving the cost of those 38 kilowatts. And yes, it does what the old system did, but the NSS has a radically different architecture’, as the computer jocks would say. You can grasp the architecture by considering a simple analog – Swedish automobile manufacture. Instead of using a single assembly line – which is vulnerable to complete failure at any point - small teams of stalwart Swedes build complete cars from start to finish.
yeah, the electrick bill…
So what’s the big deal?
Well, the NSS is more than just a replacement for the old system (which, in addition to constant cooling, also required a lot of maintenance.) It’s considerably more reliable… and reliability is important when you’re on the telescope, and every minute is precious. When a PDM fails, scrutiny of the heavens proceeds with the other PDMs. The chance of catastrophic failure that would stop observing is reduced.
As an astronomer who actually sits in front of the glowing ensemble of screens that control the telescope, I experience first-hand the advantages of the NSS. This is far more than a hardware upgrade: the software has also been rewritten. I can now quickly look at incoming signals that are being checked out. Do they look like satellites, or radar, or…? What’s their strength? Their drift rate? Autopilot is nice, but to really get the feel of the craft, you have to poke and pull at the controls.
“This is the most complex project I’ve ever worked on,” says Tom Kilsdonk, a tall, soft-spoken software developer who’s been crafting code for the NSS for five years. “I’ve got to say that it’s really exciting to see a plan come together.”
Mike Davis, Director of SETI Projects for the SETI Institute, and a former Director of the Arecibo Observatory, is less restrained. “This is impressive as hell,” he says. “It shows the real benefits of an object-oriented programming approach.”
Not having visited hell yet, I cannot fully gauge Davis’ comparison. But seeing signals pour down the flat panel monitors of the NSS I feel as if I’m “taking the con” on a high-tech ship of discovery.
Greetings from Germany
Ulli
