"Another indication of that is the thirty-year delay," added Ferrati. "Obviously, they arrived in this solar system from somewhere outside it. We figure that way because otherwise they would have been prepared to do the job on all the planets in the same trip and start operations at once. They must have made some observations of this solar system from a point in space at least as far away as another star. That means not less than four and a half light-years away--Proxima Centauri being the nearest star after our Sun, and four and a half light-years from us. Their observations were imperfect. They found more planets and problems than they had supposed. So they had to make a second trip to get enough supplies to finish their Sun-tap base constructions. It took them thirty years between the first stations and the ones that completed the job. "And that, too, suggests that only one ship was originally involved here. Of course, maybe they came back with more the second time, but it still looks as if the main force hasn't arrived. And won't, until after the Sun novas." "Then that means," said Burl quickly, "that we are still dealing with just a small and isolated group?" "Maybe," said Haines. "Just what constitutes a small group may be hard to say. I rather think they'd have brought the engineers and at least an advance working party of settlers with them the second trip in. But they are still short of available ships--they're still not aware of what we may be going to do." "Why is that?" asked Burl. Haines looked thoughtful. "This is conjecture. But if they planted any spies among our Earth people, there's been no contact, because otherwise they'd have known we could track and crack their base as soon as it started. This means that they still haven't had scouting ships to spare for checking up on what they did the first time. No checkup means no spare personnel to do the checking. They just assumed that we hadn't caught on, and started operations by remote control as they had originally planned." "And that also may mean that these people are hard up," said Ferrati. "Wherever they came from, their civilization has been great, but it's gone to seed. They plan to seize another solar system, start over again, and they haven't the manpower to do an adequate job--and they haven't the abundance of material needed to set up simple check and guard stations, such as any major Earth nation would have the sense to do." "Why, that means we've got a fighting chance to lick 'em," said Burl joyfully. "I kept thinking we'd run into more than we could cope with." "We've got a fighting chance, all right," said Haines. "We may be able to rip up their Sun-tap layouts, but what if we meet the main explorer ship itself? Anybody who can cross interstellar space and warp the power of the Sun, can probably outshoot, outrun, and outfight us. Let's hope we don't meet them until we've done our work."