But that comfortable assumption had just become inoperable. "Closed" warp points were far less common than "open" ones - or, at least, astrographers had traditionally assumed they were. It was hard to be positive, since the only way to locate a closed point was to come through it from an open one at the far end of the link, and the latest models suggested closed points might in fact occur much more frequently than previously assumed. Indeed, the more recent math predicted that the conditions which created such warp points in the first place would tend to put closed points at both ends of a link.

If true, there could be hundreds of undetectable warp lines threaded all through explored space, but what mattered just now was that the discovery that Indra's open warp point connected to a closed one here automatically upgraded SF 27's mission status. If no one could even find the thing, the fact that no one had come through it meant nothing, so the possibility of meeting another advanced species increased exponentially. Star-traveling races were rare. So far humanity had encountered barely half a dozen of them, but some of those encounters had been traumatic, and Survey Command's operational doctrine had been established as far back as the First Interstellar War. The first responsibility of any Survey ship was to report the existence of such a race before attempting to make contact, and the second was to see to it that no potentially hostile species learned anything about the Federation's astrography until formal contact - and the newcomers' bona fides - had been established. The best way to accomplish both those ends was to be sure no newly encountered race even knew the survey force was present until it had been observed at length, which was the reason the Hun-class mounted cloaking ECM.