Using graphics processing units (GPUs) to watch the heavens.

As gamers, we sometimes marvel at the visual treats our GPUs provide us in our games. Few realize, however, just what a powerhouse of processing power modern graphics cards can be. I've had blog entries highlighting some uses of these "general purpose" capabilities of GPUs aside from their normal roles as rendering hardware.

A new paper "Accelerating Radio Astronomy Cross-Correlation with Graphics Processing Units" demonstrates a novel use of the hardware capabilities of modern GPUs (in this case, units from the Nvidia line of Tesla and standard GPUs) to accelerate the cross-correlation of interferometric data from radio telescope arrays. For those not familiar with this technique, allowing an array of telescopes to resolve at the level of a telescope the size of the array (implausibly large to actually realize - arrays can span arbitrary distances), a quick look at the Wikipedia article "Interferometry" provides a high-level refresher.

Even readers without a mathematical inclination should find the paper accessible, though a full understanding will require very basic calculus. There is a minor mistake on page 9, a confusion over 8b/10b encoding, that has no material effect on the contents of the paper. These are astrophysicists, not computer scientists...

Rob