And therein lay the problem. Or, at least, one of the problems.
The Junction was almost seven light-hours from Manticore-A. Which meant any fleet stationed to cover the Junction was light-hours away from the planets on which the vast majority of Queen Elizabeth III's subjects happened to live. As the man charged with protecting those subjects, that was... inconvenient for one Sebastian D'Orville.
The Junction's position also put it over eleven light-hours from Manticore-B, which created Home Fleet's commander's second problem. But, fortunately, Manticore-B also lay far outside the resonance zone-volume of space between the Junction and Manticore-A in which it was virtually impossible to translate between normal-space and hyper-space. Any wormhole terminus associated with a star formed a conical volume in hyper, with the wormhole at its apex and a base centered on the star and twice as wide as its hyper limit, in which astrogation was extraordinarily difficult and dangerous. The bigger the terminus, the stronger the resonance effect... and the Manticoran Wormhole Junction was the largest ever discovered. The resonance wave it produced was more of a tsunami, and it didn't just make astrogation "difficult." It made it the next best thing to flatly impossible, and any transition within the resonance (assuming someone could have plotted one in the first place) would have been no more than a complicated way to commit suicide. But since the Manticore Binary System's secondary component lay outside the resonance (and would for the next few hundred years or so), Home Fleet had actually been closer from its position covering the Junction-in terms of travel time-to Manticore-B than to Manticore-A.
As for Manticore-A, the planets of Manticore and Sphinx-Home Fleet's major inner-system defensive obligations-had been well inside the same resonance zone when he took up command of Home Fleet, with Manticore, with its smaller orbital radius, steadily "overtaking" Sphinx as it moving towards opposition. Each planet spent half its year inside the zone, and Sphinx's year was more than five T-years long. That meant it took thirty-one T-months to cross through the RZ, and it had been almost in the middle of the zone when he took up his command.
Actually, Sphinx's position was the third, and in many ways worst, problem confronting any Home Fleet CO, because the planet's orbital radius was only 15.3 million kilometers-less than nine-tenths of a light-minute-shorter than the GO primary's twenty-two-light-minute hyper limit. In an era of MDMs, that meant an attacker could translate out of hyper with the planet, and its entire orbital infrastructure, already fifty million kilometers inside his missile range. Even a conventionally armed fleet, with old-style compensators, and a relative velocity on translation of zero, could have achieved a zero/zero intercept with the planet in under an hour. A fleet of superdreadnoughts with modern Alliance compensators could have done it in barely fifty minutes.
Which, all things considered, didn't leave the system defenses' commander a lot of time in which to react.
But with Sphinx so deep inside the zone, he'd actually had much more defensive depth. He'd still been able, at least in theory, to cover both habitable planets from his position at the Junction, since he could have micro-jumped away from the Junction (and the primary) and then jumped back in close enough to come in behind any fleet moving in on either planet. He would have found it difficult to actually overtake the attackers, perhaps, but the range of his MDMs would have compensated for that. And because it would have taken the attacker longer to reach engagement range of his target, Home Fleet had had time to make those jumps. In theory, at least.
But theory, as Sebastian D'Orville had learned over the years, had a nasty habit of biting one on the backside at the most inopportune moment. That was why he'd never really been happy with his enforced deployment. And now that Sphinx would clear the RZ in less than four T-months, he was even less comfortable with hanging his fleet on the Junction. The planet had lost too much of the additional "depth" the zone had created for him, and even in a best-case scenario, his need to make two separate hyper translations from the Junction would have placed him well astern of his hypothetical attacker, since he couldn't make even the first of them until after the aggressor force arrived and started accelerating towards its targets.
In effect, Home Fleet had been isolated from the rest of the inner-system's defenses, because any attacking fleet would be between D'Orville's ships and the fixed defenses which were supposed to support it. And that attacking fleet would have been able to begin building an acceleration advantage towards its objectives while Home Fleet was still getting itself organized.
Under those circumstances, an attacker without the strength to defeat both Home Fleet and the inner defenses together might well still have the strength to turn on Home Fleet-which would have no option but to pursue him-and crush it in a separate, isolated engagement.
Which was why D'Orville was so relieved the new forts were finally operational. Much smaller than the old prewar fortifications which had been decommissioned to provide the manpower to crew new construction, they were actually more powerfully armed, thanks to the same increased automation and weapons developments which had gone into the Navy's new warships. And each of those forts was surrounded by literally hundreds of missile pods, with the fire control to handle stupendous salvos. It would take an attack in overwhelming force to break those defenses, which had freed D'Orville to move Home Fleet closer to a more traditional covering position, locating his command in Sphinx orbit.
His new station provided Sphinx with badly needed, close-in protection. And with the planet of Manticore still trailing its orbital position, and so still deeper into the zone and (as always) further inside the hyper-limit, he was actually better placed to cover Manticore than he would have been anywhere else. Any least-time course to Manticore would require the attacker to get past his position at Sphinx, first, and he could easily intercept the opposing fleet short of its objective.
The solution wasn't perfect, of course. For one thing, the move left Manticore-B and its inhabited planet of Gryphon more exposed then it had been when Home Fleet was stationed at the Junction, since D'Orville would now have to get clear of the zone before he could hyper out to the system's secondary component. But the extra danger wasn't very great, now that Sphinx was within eight light-minutes of the zone's boundary. And more vulnerable or not, Gryphon had the smallest population and industrial base of any of the Star Kingdom's original inhabited worlds. If something had to be exposed, cold logic said Gryphon was a better choice than the other two planets, and the Admiralty had compensated as best it could by assigning the buildup of Manticore-B's fixed defenses a higher priority than Manticore-A's. In fact, Manticore-B's forts and space station were already refitting with Keyhole II and would begin deploying the first of the system-defense Apollo pods within the nest three weeks, on the theory that it would need them worse since it couldn't call as readily on Home Fleet's protection.
And once Manticore-B's defenses were fully up to speed, Sphinx would receive the next highest priority, despite the fact that the planet of Manticore had the largest population and the greatest economic and industrial value of any of the binary system's worls. Like Manticore-B, Sphinx was simply more exposed than Manticore.
D'Orville agreed with both those decisions, although that didn't mean he was happy about the policy they implied. It was simply, in his opinion, the best of several options, none of which could have been completely acceptable. And at least the Strategy Board's decision that Gryphon would have to look after itself instead of relying upon immediate intervention by Home Fleet had enormously simplified D'Orville's responsibilities and problems.