The Very Dangerous Array, or VDA, is not so much a technology as a technique. Creating a VDA is a matter of augmenting a missile-control computer with astronomy programming, and then using the missiles' targeting sensors as nodes of a Very Large Array-style aperture-synthesis telescope . Since any warship worth its hullmetal carries hundreds of terapedoes, and these can be spread across an immense area, the technique creates an astoundingly high-resolution telescope with virtually no effort. And of course, if you happen to spot an enemy with this telescope, by definition you've already fired a barrage of missiles at them.
A VDA also has the advantage that it can be teraported to various distances from a target and report its view in real time via hypernet. In this way, the user of the array can bypass speed-of-light lag when observing a distant target, or even exploit that lag to examine a target's history. For example, a VDA positioned twelve light-hours away from a site will see what happened there twelve hours ago.