"I believe this expedition was just an exploratory one; and if they can send such huge machines and so many of them, for mere exploration, I'm sure they must have quite a fleet to fight with.

"We know little about their weapons. They have that death ray, but it's not quite as deadly as we might have feared, solely because our ships could outmaneuver them. Next time, logically, they'll bring with them a fleet of little ships, carried in the bellies of those giants, and they'll be a real enemy. We'll have to anticipate their moves and build to circumvent them.

"As for their ray, I believe I have an idea how it works. You're all familiar with the catalytic effects of light. Hydrogen and chlorine will stand very peacefully in the same jar for a long time, but let a strong light fall on them, and they combine with terrific violence. This is the catalytic effect of a vibration, a wave motion. Then there is such a thing as negative catalysis. In a certain reaction, if a third element or compound is introduced, all reaction is stopped. I believe that's the principle of the Nigran death ray; it's a catalyst that simply stops the chemical reactions of a living body, and these are so delicately balanced that the least resistance will upset them."

Arcot halted, and sat puffing furiously for a moment. During his discourse the pipe had died to an ember; with vigorous puffing he tried to restore it. At last he had it going and continued.

"What other weapons they have we cannot say. The secret of invisibility must be very old to them. But we'll guard against the possibility by equipping our ships against it. The only reason the patrol ships aren't equipped already is that invisibility is useless with modern criminals; they all know the secret and how to fight it."

Morey interrupted with a question.

"Arcot, it's obvious that we have to get out into space to meet the enemy—and we'll have to have freedom of movement there. How are we going to do it? I was wondering if we could use Wade's system of storing the atomic hydrogen in solution. That yields about 100,000 calories for every two grams, and since this is a method of storing heat energy, and your molecular motion director is a method of converting heat into mechanical work with 100 per cent efficiency, why not use that? All we need, really, is a method of storing heat energy for use while we're in space."

Arcot exhaled slowly before answering, watching the column of smoke vanish into the air.

"I thought of that, and I've been trying to think of other, and if possible, better, cheaper, and quicker ways of getting the necessary power.

"Let's eliminate the known sources one by one. The usual ones, the ones men have been using for centuries, go out at once. The atomic hydrogen reaction stores more energy per gram than any other chemical reaction known. Such things as the storage battery, the electro-static condenser, the induction coil, or plain heat storage, are worthless to us. The only other method of storing energy we know of is the method used by the Kaxorians in driving their huge planes.

"They use condensed light-energy. This is efficient to the ultimate maximum, something no other method can hope to attain. Yet they need huge reservoirs to store it. The result is still ineffective for our purpose; we want something we can put in a small space; we want to condense the light still further. That will be the ideal form of energy storage, for then we will be able to release it directly as a heat ray, and so use it with utmost efficiency. I think we can absorb the released energy in the usual cavity radiator."

A queer little smile appeared on Arcot's face. "Remember—what we want is light in a more condensed form, a form that is naturally stable, and that does not need to be held in a bound state, but actually requires urging to bring about the release of energy. For example—"

A shout from Wade interrupted him. "That's really rare! Whoo—I have to hand it to you! That takes all the prizes!" He laughed delightedly. In puzzled wonder Morey and the two older men looked at him, and at Arcot who was grinning broadly now.

"Well, I suppose it must be funny," Morey began, then hesitated. "Oh—I see—say, that is good!" He turned to his father. "I see now what he's been driving at. It's been right here under our noses all the time.

"The light-matter windows we found in the wrecked enemy ships contain enough bound light-energy to run all the planes we could make in the next ten years! We're going to have the enemy supply us with power we can't get in any other way. I can't decide, Arcot, whether you deserve a prize for ingenuity, or whether we should receive booby-prizes for our stupidity."

Arcot Senior smiled at first, then looked dubiously at his son.

"There's definitely plenty of the right kind of energy stored there—but as you suggested, the energy will need encouragement to break free. Any ideas?"

"A couple. I don't know how they'll work, of course; but we can try." Arcot puffed at his pipe, serious now as he thought of the problems ahead.

Wade interposed a question. "How do you suppose they condense that light energy in the first place, and, their sun being dead, whence all the light? Back to the atom, I suppose."

"You know as much as I do, of course, but I'm sure they must break up matter for its energy. As for the condensation problem, I think I have a possible solution of that too—it's the key to the problem of release. There's a lot we don't know now—but we'll have a bigger store of knowledge before this war is over—if we have anything at all!" he added grimly. "It's possible that man may lose knowledge, life, his planets and sun—but there's still plenty of hope. We're not finished yet."

"How do you think they got their energy loose?" asked

Wade. "Do you think those big blocks of what appeared to be silver were involved in the energy release?"

"Yes, I do. Those blocks were probably designed to carry away the power once it was released. How the release was accomplished, though, I don't know. They couldn't use material apparatus to start their release of material energy; the material of the apparatus might 'catch fire' too. They had to have the disintegrating matter held apart from all other matter. This was quite impossible, if you are going to get the energy away by any method other than by the use of fields of force. I don't think that is the method. My guess is that a terrific current of electricity would accomplish it if anything would.

"How then are we going to get the current to it? The wires will be subject to the same currents. Whatever they do to the matter involved, the currents will do to the apparatus—except in one case. If that apparatus is made of some other kind of matter, then it wouldn't be affected. The solution is obvious. Use some of the light-matter. What will destroy light-matter, won't destroy electricity-matter, and what will destroy electricity-matter, won't disturb light-matter.

"Do you remember the platform of light-metal, clear as crystal? It must have been an insulating platform. What we started as our assumptions in the case of the light-metal, we can now carry further. We said that electricity-metals carried electricity, so light-metals would carry or conduct light. Now we know that there is no substance which is transparent to light, that will carry electricity by metallic conduction. I mean, of course, that there is no substance transparent to light, and at the same time capable of carrying electricity by electronic transmission. True, we have things like NaCl solutions in ordinary H_{2}O which will carry electricity, but here it's ionic conduction. Even glass will carry electricity very well when hot; when red hot, glass will carry enough electricity to melt it very quickly. But again, glass is not a solid, but a viscous liquid, and it is again carried by ionic conduction. Iron, copper, sodium, silver, lead—all metals carry the current by means of electron drift through the solid material. In such cases we can see that no transparent substance conducts electricity.

"Similarly, the reverse is true. No substance capable of carrying electricity by metallic conduction is transparent. All are opaque, if in any thickness. Of course, gold is transparent when in leaf form—but when it's that thin it won't conduct very much! The peculiar condition we reach in the case of the invisible ship is different. There the effects are brought about by the high frequency impressed. But you get my point.

"Do you remember those wires that we saw leading to that little box of the reflecting material? So perfectly reflecting it was that we didn't see it. We only saw where it must be; we saw the light it reflected. That was no doubt light-matter, a non-metal, and as such, non-conductive to light. Like sulphur, an electric non-metal, it reflected the base of which it was formed. Sulphur reflects the base of which it was formed. Sulphur reflects electricity and—in the crystalline form—passes light. This light-non-metal did the same sort of thing; it reflected light and passed electricity. It was a conductor.

"Now we have the things we need, the matter to disintegrate, and the matter to hold the disintegrating material in. We have two different types of matter. The rest is obvious—but decidedly not easy. They have done it, though; and after the war is over, there should be many of their machines drifting about in space waiting to give up their secrets."

Arcot Senior clapped his son on the back. "A fair foundation on which to start, anyway. But I think it's time now that you got working on your problem; and since I'm officially retired, I'm going downstairs. You know I'm working in my lab on a method to increase the range and power of your projector for the molecular motion field. Young Norris is helping me, and he really has ideas. I'll show you our math later."

The party broke up, the three younger men staying in their own labs, the older men leaving.



IV

The three immediately set to work. At Arcot's suggestion, Wade and Morey attacked the plate of crystal in an attempt to tear off a small piece, on which they might work. Arcot himself went into the televisophone room and put through a second call to the Tychos Observatory, the great observatory that had so recently been established on the frigid surface of the Moon. The huge mirror, twenty feet in diameter, allowed an immense magnification, and stellar observations were greatly facilitated, for no one bothered them, and the "seeing" was always perfect.

However, the great distance was rather a handicap to the ordinary televisophone stations, and all calls put through to the astronomers had to be made through the powerful sending station in St. Louis, where all interplanetary messages were sent and received, while that side of the Earth was facing the station; and from Constantinople, when that city faced the satellite. These stations could bridge the distance readily and clearly.

For several minutes Arcot waited while connections were being made with the Moon; then for many more minutes he talked earnestly with the observer in this distant station, and at last satisfied, he hung up.

He had outlined his ideas concerning the black star, based upon the perturbation of the planets; then he had asked them to investigate the possibilities, and see if they could find any blotting out of stars by a lightless mass.

Finally he returned to Morey and Wade who had been working on the crystal plate. Wade had an expression of exasperation on his face, and Morey was grinning broadly.

"Hello, Arcot—you missed all the fun! You should have seen Wade's struggle with that plate!" The plate, during his absence, had been twisted and bent, showing that it had undergone some terrific stresses. Now Wade began to make a series of highly forceful comments about the properties of the plate in language that was not exactly scientific. It had value, though, in that it seemed to relieve his pent-up wrath.

"Why, Wade, you don't seem to like that stuff. Maybe the difficulty lies in your treatment, rather than in the material itself. What have you tried?"

"Everything! I took a coronium hack saw that will eat through molybdenum steel like so much cheese, and it just wore its teeth off. I tried some of those diamond rotary saws you have, attached to an electric motor, and it wore out the diamonds. That got my goat, so I tried using a little force. I put it in the tension testing machine, and clamped it—the clamp was good for 10,000,000 pounds—but it began to bend, so I had to quit. Then Morey held it with a molecular beam, and I tried twisting it. Believe me, it gave me real pleasure to see that thing yield under the pressure. But it's not brittle; it merely bends.

"And I can't cut it, or even get some shavings off the darned thing. You said you wanted to make a Jolly balance determination of the specific gravity, but the stuff is so dense you'd need only a tiny scrap—and I can't break it loose!" Wade looked at the plate in thorough disgust.

Arcot smiled sympathetically; he could understand his feelings, for the stuff certainly was stubborn. "I'm sorry I didn't warn you fellows about what you'd run into, but I was so anxious to get that call through to the Moon that I forgot to tell you how I expected to make it workable. Now, Wade, if you'll get another of those diamond-tooth rotary saws, I'll get something that may help. Put the saw on the air motor. Use the one made of coronium."

Wade looked after the rapidly disappearing Arcot with raised eyebrows, then, scratching his head, he turned and did as Arcot had asked.

Arcot returned in about five minutes with a small handling machine, and a huge magnet. It must have weighed nearly half a ton. This he quickly connected to the heavy duty power lines of the lab. Now, running the handling machine into position, he quickly hoisted the bent and twisted plate to the poles of the magnet, with the aid of the derrick. Then backing the handling machine out of the way, he returned briskly to his waiting associates.

"Now we'll see what we will see!" With a confident smile Arcot switched on the current of the big magnet. At once a terrific magnetic flux was set up through the light-metal. He took the little compressed-air saw, and applied it to the crystal plate. The smooth hiss of the air deepened to a harsh whine as the load came on it, then the saw made contact with the refractory plate.

Unbelievingly Wade saw the little diamond-edge saw bite its way slowly but steadily into the plate. In a moment it had cut off a little corner of the light-matter, and this fell with a heavy thud to the magnet pole, drawn down by the attraction of the magnet and by gravity.

Shutting off the magnet, Arcot picked up a pair of pliers and gripped the little fragment.

"Whew—light-metal certainly isn't light metal! I'll bet this little scrap weights ten pounds! We'll have to reduce it considerably before we can use it. But that shouldn't be too difficult."

By using the magnet and several large diamond faceplates they were able to work the tough material down to a thin sheet; then with a heavy press, they cut some very small fragments, and with these, determined the specific gravity.

"Arcot," Wade asked finally, "just how does the magnet make that stuff tractable? I'm not physicist enough to figure out what takes place inside the material."

"Magnetism worked as it did," Arcot explained, "because in this light-matter every photon is affected by the magnetism, and every photon is given a new motion. That stuff can be made to go with the speed of light, you know. It's the only solid that could be so affected. This stuff should be able, with the aid of a molecular motion beam, which will make all the photons move in parallel paths, to move at the full speed of each photon—186,000 miles a second. The tremendous speed of these individual photons is what makes the material so hard. Their kinetic impulse is rather considerable! It's the kinetic blow that the molecules of a metal give that keeps other metal from penetrating it. This simply gives such powerful impulse that even diamonds wouldn't cut it.

"You know that an iron saw will cut platinum readily, yet if both are heated to say, 1600 degrees, the iron is a liquid, and the platinum very soft—but now the platinum cuts through the iron!

"Heat probably won't have any effect on this stuff, but the action of the magnet on the individual photons corresponds to the effect of the heat on the individual atoms and molecules. The mass is softened, and we can work it. At least, that's the way I figure it out.

"But now, Wade, I wish you'd see if you can determine the density of the stuff. You're more used to those determinations and that type of manipulation than we are. When you get through, we may be able to show you some interesting results ourselves!"

Wade picked up a tiny chip of the light-metal and headed for his own laboratory. Here he set up his Jolly balance, and began to work on the fragment. His results were so amazing that he checked and rechecked his work, but always with the same answer. Finally he returned to the main lab where Arcot and Morey were busy at the construction of a large and complicated electro-static apparatus.

"What did you find?" called out Arcot, as he saw Wade reenter the room. "Hold your report a second and give us a hand here, will you? I have a laboratory scale apparatus of the type the Kaxorians used in the storage of light. They've known, ever since they began working with them, that their machines would release the energy with more than normal violence, if certain changes were made in them. That is, the light condenser, the device that stored the photons so close to each other, would also serve to urge them apart. I've made the necessary changes, and now I'm trying to set up the apparatus to work on solid light-matter. It was developed for gaseous material, and it's a rather tricky thing to change it over. But I think we've almost got it.

"Wade, will you connect that to the high frequency oscillator there—no—through that counterbalanced condenser. We may have to change the oscillator frequency quite a bit, but a variable condenser will do that.

"Now, what results did you get?"

Wade shook his head doubtfully. "We all know it's amazing stuff—and of course, it must be heavy—but still—well, anyway, I got a density of 103.5!"

"Whewww—103.5! Lord! That's almost five times as heavy as the heaviest metal hitherto known. There's about half a cubic foot of the material; that would mean about 4000 pounds for the whole mass, or two tons. No wonder we couldn't lift the plate!"

They stopped their work on the Kaxorian apparatus to discuss the amazing results of the density test, but now they fell to again, rapidly assembling the device, for each was a trained experimenter. With all but the final details completed, Arcot stood back and surveyed their handiwork.

"I think we'll have enough urge to cause disintegration right here," he said, "but I want to make sure, and so, before we set up the case over it, I think we may as well put that big magnet in place, and have it there to help in the work of disintegration, if need be."

At last the complete apparatus was set up, and the tiny bit of light-matter they were to work on was placed on the table of a powerful Atchinson projector microscope, the field of view being in the exact center of the field of both the magnet and the coil. Carefully, then, step by step, Arcot, Morey and Wade went over their work, checking and rechecking.

"Well, we're ready," said Arcot finally, as he placed the projector screen in position and dimmed the lights in the room. A touch of the switch, and the projection screen was illuminated with the greatly enlarged image of the tiny scrap of light-metal.

With his hand on the switch, Arcot spoke to the other two. "I won't say there's no danger, since we haven't done this before; and if all the energy should be released at once, it'll blow the top out of the building. But I'm reasonably sure that it will work safely. Any objections?"

Wade shook his head, and Morey said: "I can't see any flaws in our work."

Arcot nodded, and unconsciously tensing, he closed the switch. This put the powerful Arcot oscillator tubes into action, and the power was ready for application.

Slowly he closed the rheostat and put the power into the coil. The little sliver of metal on the slide seemed to throb a bit, and its outline grew hazy; but at last, with full power on, the release was so slow as to be imperceptible.

"Guess we need the magnet after all; I'll put it on this time."

He opened the coil circuit and closed the magnet circuit at half voltage, then again he increased the current through the rheostat. This time the plate throbbed quite violently, it took the appearance of a bit of iodine. Dense vapors began pouring from it, and instantly those vapors became a blindingly brilliant flood of light. Arcot had snapped open the switch the moment he saw this display start, and it had had little time to act, for the instant the circuit was opened, it subsided. But even in that brief time, the light aluminum screen had suddenly become limp and slumped down, molten! The room was unbearably hot, and the men were half blinded by the intensity of the light.

"It works!" yelled Wade. "It works! That sure was hot, too—it's roasting in here." He flung open a window. "Let's have some air."

Arcot and Morey gripped hands with a broad grin. That display meant that Earth and Venus would have space ships with which to fight space ships. Reason enough for their joy.

Though they had made an unusual amount of progress already, there was still a great deal of development work to be done. Fuller was needed, Arcot decided, so he called the elder Morey and requested his services if he could be spared from his present work. He could, and would arrive later that day.

When Fuller appeared about mid-afternoon, he found the three friends already at work on the development of a more compact apparatus than the makeshift hookup used in making that first release mechanism.

"And so you can see," said Arcot as he finished his summary of their work to that point, "we still have quite a job ahead of us. I'm now trying to find some data for you to work on, but I can tell you this: We'll need a ship that has plenty of strength and plenty of speed. There will be the usual power plant, of course; the generators, the power-tube board, and the electro-magnetic relays for the regular molecular motion controls. Then, in addition, we must have controls for the ray projector, though that must wait a while, for Dad is working on a method of doubling our range.... Oh yes, the driving units will be inside the ship now, for all our power will come from the energy of the light-matter."

They spent the next hour in discussing the manifold details involved in the design of their space ship: the mechanism involved in transferring the light-energy to the drivers; a means of warming the ship in interstellar space; a main horizontal drive for forward and backward motion as well as braking; three smaller vertical power units to give them freedom of direction in climb or descent; other smaller horizontal power units for turning and moving sideways.

The ships, they decided, must be capable of six or seven thousand miles a second. They would need three types of ships: a small single-man speedster, without bunk or living quarters, simply a little power plant and weapon. Designed for speed and mobility, it would be very hard to hit, and because of its own offensive power would be dangerous to the enemy. They would need a fleet of mother ships—ships that would hold both the speedsters and their pilots—say thirty to a cruiser. There would also be some ten-man scouts, operating in the same manner as the larger cruisers, but with a smaller fleet of speedsters dependent on them.

"For defense," Arcot concluded, "we'll have to depend on armor as heavy as we can make and still remain within the bounds of practical construction. I don't believe we'll be able to build up enough mass to insulate against their negative catalysis ray. We'll have to depend on mobility and offense.

"But now let's get back to work. I think, Fuller, that you might call in the engineers of all the big aircraft and machine tool manufacturers and fabricators, and have them ready to start work at once when the plans are finally drawn up. You'd better get in touch with the Venerian producers, too. Those new works in Sorthol, Kaxor, will certainly be able to help a lot.

"I suppose the Interplanetary Patrol men will have something to say, so they better be called in. Likewise the Venerian Council. Morey, maybe your dad can handle some of this."

As one they arose and set to work on their respective tasks—the planning and building of the Earth-Venus war fleet.



V

Despite their utmost endeavor and the hard work of the industrial might of two worlds, it was nearly six weeks before the fleet had grown to a thing of importance. The tests to which they subjected the tiny speedsters had been more than satisfactory. They behaved wonderfully, shooting about at terrific speed, and with all the acceleration a pilot could stand. These speedsters were literally piloted projectiles, and their amazing mobility made them a powerful arm of offense.

There came into being a special corp dubbed, oddly enough, the "Rocket Squad", a group of men who could stand plenty of "G's". This "Rocket Squad" was composed solely of Terrestrians, for they were accustomed to the gravity of Earth and could stand greater acceleration strains than could the Venerians. The pick of the Air Patrol formed the nucleus of this new military organization; and in short order, so great is the appeal of the new and novel, the cream of the young men of the planet were competing for a place among the Rocketeers.

Each ship, both speedster and mother craft, was equipped with an invisibility locator, a sensitive short-wave directional receiver, that would permit the operator to direct his rays at invisible targets. The ships themselves could not be made invisible, since they depended in their very principle on the absorption of light-energy. If the walls of every part of the ship were perfectly transparent, they could absorb no energy at all, and they would still be plainly visible—even more so than before! They must remain visible, but they could also force the enemy to remain visible.

Each ten-man ship carried an old-fashioned cannon that was equipped to hurl cannisters carrying the luminous paint. They decided that these would have advantages, even if the invaders did not use invisibility, for in space a ship is visible only because it reflects or emits light. For this reason the ships were not equipped with any portholes except in the pilot room and at the observation posts. No light could escape. To reduce the reflection to the absolute minimum, the ships had each been painted with a 99% absorptive black. In space they would be exceedingly difficult targets.

The heating effect of the sun on the black pigment when near the great star was rather disagreeably intense, and to cool the speedsters they had installed molecular director power units, which absorbed the heat and used the energy to drive the ship. Heaters offset the radiation loss of the black surface when too far from the sun.

Each of the speedsters was equipped with a small machine-gun shooting luminous paint bullets. One of these, landing on another craft, made it visible for at least two hours, and since they could cover an area of about thirty feet, they were decidedly effective.

It was found that ray practice was rather complicated. The government had ranges set up in great mountain districts away from any valuable property, but they soon found that spatial warplay could not be carried on on Earth. The rays very quickly demolished the targets, and in a short time made good progress toward demolishing the mountains as well. The problem was solved by using the barren surface of the moon and the asteroid belt beyond Mars as a proving ground.

The ships were sent out in squadrons as fast as they could be finished and the men could be brought together and trained. They were establishing a great shield of ships across all that section of the system whence the Nigrans had appeared, and they hoped to intercept the next attack before it reached Earth, for they were certain the next attack would be in full force.

Arcot had gone to the conference held on Venus with the other men who had investigated the great wrecks, and each scientist had related his view of things and had offered suggestions. Arcot's idea of the black star was not very favorably received. As he later told Wade and Morey, who had not gone, there was good reason for their objection to his idea. Though the scientists were willing to admit that the invaders must have come from a great distance, and they agreed that they lived in an atmosphere of hydrogen, and judging from their pale skins, that they were not used to the rays of a sun, they still insisted on the theory of an outer planet of Sol.

"You remember," explained Arcot, "several years ago there was considerable discussion about the existence of a planet still further out from the sun than Pluto. It is well known that there are a number of irregularities in the orbits of Neptune and Pluto that can't be caused by known planets, and an outer planet could have the necessary mass and orbit to account for them.

"This attack from outer space was immediately taken as proof of that theory, and it was very easily supported, too. My one good point that stood for any length of time under their attacks was the fact that those ships weren't developed in a year, nor a century, and that the chemical constitution of the men was so different. There were no new elements discovered, except the light-matter, but they are rather wondering about the great difference of earthly chemical constitution and the constitution of these invaders.

"They had one argument that was just about enough to throw mine out, though they pointed to the odds against the thing happening. You know, of course, how planets are formed? They are the results of tidal action on two passing suns.

"You can imagine two mighty stars careening through space and then drawing slowly nearer, till at last they come within a few billion miles of each other, and their gigantic masses reach out and bind them with a mighty chain of gravity. Their titanic masses swing about each other, each trying to pull free, and continue its path about the center of the galactic system. But as their huge bulks come nearer, the chains that bind them become stronger and stronger, and the tremendous pull of the one gargantuan fire ball on the other raises titanic tides of flame. Great streamers of gas shoot out, and all the space about is lighted by the flaming suns. The pull of gravity becomes more and more intense, and as the one circles the other, the tide is pulled up, and the mighty ball of fire, which, for all its existence has been practically motionless as far as rotation goes, begins to acquire a greater and greater rotational speed as the tidal drag urges it on. The flames begin to reach higher and higher, and the tides, now urged from the sun by centrifugal force, rise into an ever greater crest, and as the swinging suns struggle to break loose, the flaming gas is pulled up and up, and becomes a mighty column of fire, a column that reaches out across three—four—a dozen millions of miles of space and joins the two stars at last, as stalactites and stalagmites grow together. A flaming tie of matter joins them, two titanic suns, and a mighty rope of fire binds them, while far mightier chains of gravity hold them together.

"But now their original velocity reasserts itself, and having spiraled about each other for who can say how long—a year—a million years seems more probable—but still only an instant in the life of a star—they begin to draw apart, and the flaming column is stretched out, and ever thinner it grows, and the two stars at last separate. But now the gas will never fall back into the sun. Like some giant flaming cigar it reaches out into space and it will stay thus, for it has been set in rotation about the sun at such a speed as is needed to form an orbit. The giant mass of gas is, however, too cool to continue to develop energy from matter, for it was only the surface of the sun, and cool. As it cools still further, there appear in it definite condensations, and the beginnings of the planets are there. The great filament that stretched from the sun to sun was cigar-shaped, and so the matter is more plentiful toward the center, and larger planets develop. Thus Jupiter and Saturn are far larger than any of the others. The two ends are tapering, thus Earth is larger than Venus, which is larger than Mercury, and Uranus and Neptune are both smaller than Saturn, Pluto being smaller than either.

"Mars and the asteroids are hard to explain. Perhaps it is easier to understand when we remember that the planets thus formed must necessarily have been rotating in eccentric orbits when they were first born, and these planets came too near the sun while gaseous, or nearly so, and Mars lost much of its matter, while the other, which now exists only as the asteroids, broke up.

"But now that other flaming star has retired, wandering on through space. The star has left its traces, for behind it there are planets where none existed before. But remember that it, too, must have planets now.

"All this happened some 2,000 million years ago.

"But in order that it might happen, it requires that two stars pass within the relatively short distance of a few billion miles of each other. Space is not overcrowded with matter, you know. The density of the stars has been compared with twenty tennis balls roaming about 8,000-mile sphere that the Earth fills up—twenty tennis balls in some 270 billion cubic miles of space. Now imagine two of those tennis balls—with plenty of room to wander in—passing within a few yards of each other. The chances are about as good as the chances of two stars passing close enough to make planets.

"Now let us consider another possibility.

"The Black Star, as I told you, has planets. That means that it must have thus passed close to another star. Now we have it coming close to another sun that has been similarly afflicted. The chances of that happening are inconceivably small. It is one chance in billions that the planets will form. Two stars must pass close to each other, when they have all space to wander about in. Then those afflicted stars separate, and one of them passes close by a new star, which has thus been similarly afflicted with that one chance in billions—well, that is then a chance in billions of billions.

"So my theory was called impossible. I don't know but what it is. Besides, I thought of an argument the other men didn't throw at me. I'm surprised they didn't, too—the explanation of the strange chemical constitution of these men of a solar system planet would not be so impossible. It is quite possible that they live on a planet revolving about the sun which is, nevertheless, a planet of another star. It is quite conceivable to me that the chemical constitution of Neptune and Pluto will be found to be quite different from that of the rest of our planets. The two filaments drawn out from the suns may not have mingled, though I think they did, but it is quite conceivable that, just before parting, our sun tore one planet, or even two or three, from the other star.

"And that would explain these strange beings.

"My other ideas were accepted. The agreed-on plan for the release of energy, and the source of the power." Arcot puffed on his pipe meditatively for several moments, then stood up and stretched.

"Ho—I wish they'd let me go on active duty with the space fleet! A scientific reputation can be an awful handicap at times," he grinned. He had been rejected very emphatically when he had tried to enlist. The Interplanetary governments had stated flatly that he was too important as a scientist to be risked as a pilot of a space ship.

On two worlds the great construction plants were humming with activity. Civilian production of all but the barest essentials had been put aside for the duration of the emergency. Space ships were being turned out at top speed, getting their fuel from the wrecks of the invaders' cruisers. Each ship needed only a small amount of the light-metal, for the energy content was tremendous. And those ships had been gigantic.

Already there was a fleet of speedsters and mother ships out there in space, and with every passing hour others left the home planets, always adding to the fighting force that was to engage the attackers deep in space, where no stray ships might filter through to destroy the cities of Earth or Venus. Assembly lines were now turning out ships so rapidly that the training of their operators was the most serious problem. This difficulty had finally been overcome by a very abbreviated training course in the actual manipulation of the controls on the home planets, and subsequent training as the squadrons raced on their outward courses.

It was soon decided that there must be another service beside that of the ordinary ships. One plant was devoted to making huge interstellar liners. These giants, made on Venus, were nearly a quarter of a mile long, and though diminutive in comparison with the giant Nigran ships, they were still decidedly large. Twelve of these could be completed within the next month, it was found; and one was immediately set aside as an officers' headquarters ship. It was recognized that the officers must be within a few hundred thousand miles of the actual engagements, for decisions would have to be made without too much loss of time in the transmission of reports.

The ship must not be brought too near the front lest the officers be endangered and the entire engagement lost for want of the organizing central headquarters. The final solution had been the huge central control ship.

The other large vessels were to be used to carry food and supplies. They were not to enter the engagement, for their huge size would make them as vulnerable to the tiny darting mites of space as the Nigran ships had been to the Interplanetary Patrol. The little ships could not conveniently stock for more than a week of engagement, then drop back to these warehouses of space, and go forward again for action.

Throughout the long wait the officers of the Solarian forces organized their forces to the limit of their ability, planning each move of their attack. Space had been marked off into a great three-dimensional map, and each ship carried a small replica, the planets moving as they did in their orbits. The space between the planets was divided off into definite points in a series of Cartesian co-ordinates, the sun being the origin, and the plane of the elliptic being the X-Y plane.

The OX line was taken pointing toward one of the brightest of the fixed stars that was in the plane of the elliptic. The entire solar system was thus marked off as had been the planets long ages before, into a system of three dimensional latitude and longitude. This was imperative, in order to assure the easy location of the point of first attack, and to permit the entire fleet to come into position there. A scattered guard was to remain free, to avoid any false attacks and a later attack from a point millions of miles distant. Earth and Venus were each equipped with gigantic ray projectors, mighty weapons that could destroy anything, even a body as large as the Moon, at a distance of ten thousand miles. Still, a ship might get through, and with the death ray—what fearful toll might be exacted from a vast city such as Chicago—with its thirty millions! Or Karos, on Venus, with its fifteen and one half millions!

The tension became greater and greater as with each passing day the populace of two worlds awaited the call from the far-flung guard. The main bulk of the fleet had been concentrated in the center of their great spherical shell of ships. They could only wait—and watch—and prepare! Hundreds of miles apart, yet near enough so that no ship except perhaps a one-man craft could pass them undetected; and behind them were ships with delicate apparatus that could detect any foreign body of any size whatever within a hundred thousand miles of them.

The Solar System was prepared to repel boarders from the vast sea of space!



VI

Taj Lamor gazed down at the tremendous field below him. In it lay close packed a great mass of ships, a concourse of Titans of Space, dreadnoughts that were soon to set out to win—not a nation, not even a world, but to conquer a solar system, and to win for their owners a vast new sun, a sun that would light them and heat them for long ages to come.

Momentarily Taj Lamor's gaze followed the retreating figure of Tordos Gar, the Elder; a figure with stooped shoulders and bowed head. His quiet yet vibrant parting words still resounded in his ears:

"Taj Lamor, remember what I tell you. If you win this awful war—you lose. As will our race. Only if you lose will you win."

With a frown Taj Lamor stared down at the vast metal hulls glistening softly in the dull light of far-off stars, the single brightly beaming star that was their goal, and the dim artificial lighting system. From the distance came to him the tapping and humming of the working machines below as they strove to put the finishing touches to the great ships.

He raised his eyes toward the far-off horizon, where a great yellow star flamed brilliantly against the black velvet of space. He thought of that planet where the sky had been blue—an atmosphere of such intensity that it colored the sky!

Thoughtfully he gazed at the flaming yellow point.

He had much to consider now. They had met a new race, barbarians in some ways, yet they had not forgotten the lessons they had learned; they were not decadent. Between his eon-old people and their new home stood these strange beings, a race so young that its age could readily be counted in millennia, but withal a strong, intelligent form of life. And to a race that had not known war for so many untold ages, it was an unthinkable thing that they must kill other living, intelligent beings in order that they might live.

They had no need of moving, Tordos Gar and many others had argued; they could stay where they were forever, and never find any need for leaving their planet. This was the voice of decadence, Taj Lamor told himself; and he had grown to hate that voice.

There were other men, men who had gone to that other solar system, men who had seen vast oceans of sparkling water, showering from their ruffled surfaces the brilliant light of a great, hot sun. They had seen towering masses of mountains that reached high into the blue sky of a natural atmosphere, their mighty flanks clothed with green growth; natural plants in abundance.

And best of all, they had fought and seen action, such as no member of their race had known in untold ages. They knew Adventure and Excitement, and they had learned things that no member of their ancient race had known for millennia. They had learned the meaning of advancement and change. They had a new ardor, a new strength, a new emotion to drive them, and those who would have held them back became enthusiasts themselves. Enthusiasm may be contagious, but the spirit of their decadence was rapidly failing before this new urge. Here was their last chance and they must take it; they would!

They had lost many men in that battle on the strange world, but their race was intelligent; they learned quickly, the small ships had been very hard targets, while their big ships were too easy to strike. They must have small ships, yet they must have large ships for cargo, and for the high speed driving apparatus. The small ships were not able to accelerate to the terrific speed needed. Once their velocity had been brought up to the desired value, it was easy to maintain it with the infinitely small friction of space as the only retarding force; one atom per cubic inch was all they must meet. This would not hold them up, but the great amount of fuel and the power equipment needed to accelerate to the desired speed could not be packed into the small ship. Into the vast holds of the huge ships the smaller ones were packed, long shining rows of little metal projectiles. Tiny they were, but they could dart and twist and turn as swiftly as could the ships they had met on that other world—tiny ships that flashed about with incredible suddenness, a target that seemed impossible to hit. These ships would be a match for those flashing motes of the Yellow Sun. Now it might be that their great transport and battle ships could settle down to those worlds and arrange them for their own people!

And they had discovered new weapons, too. One of their mightiest was a very old apparatus, one that had been forgotten for countless ages. A model of it was in existence in some forgotten museum on a deserted planet, and with it long forgotten tomes that told of its principles, and of its consequences. Invisibility was now at their command. It was an ancient weapon, but might be exceedingly effective!

And one other. They had developed a new thing! They had not learned of it in books, it was their invention! They did not doubt that there were other machines like it in their museums, but the idea was original with them. It was a beam of electrical oscillatory waves, projected with tremendous energy, and it would be absorbed by any conductor. They could melt a ship with this!

And thus that great field had been filled with Giants of Space! And in each of these thousand great warships there nestled three thousand tiny one-man ships.

Here was a sight to inspire any race!

Taj Lamor watched as the last of the working machines dragged its slow way out of the great ships. They were finished! The men were already in them, waiting to start, and now there was an enthusiasm and an activity that had not been before; now the men were anxious to get that long journey completed and to be there, in that other system!

Taj Lamor entered his little special car and shot swiftly down to the giant cruisers. He stepped out of his little craft and walked over to the tube conveyor ready for the trip to the nose of the great vessel. Behind him attendants quickly moved his car to a locked cradle berth beside long rows of similar vehicles.

A short while later those who were to remain on the dark planet saw the first of the monsters of space rise slowly from the ground and leap swiftly forward; then as methodically as though released by automatic machinery, the others leaped in swift pursuit, rushing across half a world to the tremendous space lock that would let them out into the void. In a long, swift column they rushed on. Then one at a time they passed out into the mighty sea of space. In space they quickly formed and set out.

As though by magic, far to the left of their flight, there suddenly appeared a similar flight of giant ships, and then to the right, and above them, another seemed to leap out of nothingness as the ships of other planets came into sight. Quickly they formed a vast cone about their leader's ship, a protecting screen, yet a powerful offensive formation.

Endlessly, it seemed, they sped on through the darkness. Then as the yellow star flamed brighter and brighter before them, they slowed their ships till the small fliers could safely be released into space.

Like a swarm of insects flying about giant birds of space the little ships circled the mighty masses of the battle cruisers. So huge were they, that in the combined mass of the fleet there rested sufficient gravitational attraction to force the little fliers to form orbits about them. And so they sped on through the void, the vast conical fleet with its slowly circling belt of little ships. A fleet whose counterpart had never entered the Solar System.

It was well beyond the orbit of Pluto that the first of the Solarian scouts detected the approaching invasion fleet. The tension that had gripped Earth and Venus and their guardian ships for so long a time suddenly snapped; and like a great machine set into sudden motion, or a huge boulder, balanced, given the last push that sends it spinning with destructive violence down a slope, the fleet went into action.

It was merely a little scout, a ten-man cruiser, that sent in the message of attack, and then, upon receiving headquarters' permission, went into action. Some of the tacticians had wanted to try to get the entire fleet into battle range for a surprise attack in power; but others felt that this could not possibly succeed. Most important, they decided, was the opportunity of learning if the invaders had any new weapons.

The Nigrans had no warning, for a ten-man cruiser was invisible to them, though the vast bulk of their own ships stood out plainly, lighted by a blazing sun. No need here to make the sun stand still while the battle was finished! There was no change out here in all time! The first intimation of attack that the Nigrans had was the sudden splitting and destruction of the leading ship. Then, before they could realize what was happening, thirty-five other destructive molecular motion beams were tearing through space to meet them! The little ten-man cruiser and its flight of speedsters was in action! Twenty-one great ships crumpled and burst noiselessly in the void, their gases belching out into space in a great shining halo of light as the sun's light struck it.

Unable to see their tiny enemies, who now were striking as swiftly, as desperately as possible, knowing that death was practically certain, hoping only to destroy a more equal number of the giants, they played their beams of death about them, taking care to miss their own ships as much as possible.

Another ship silently crumpled, and suddenly one cruiser right in the line of the flight was brought to a sudden halt as all its molecules were reversed. The ships behind it, unable to stop so suddenly, piled up on it in chaotic wreckage! A vast halo of shining gas spread out fifty thousand miles about, blinding further the other ships, the radiance about them making it impossible to see their tiny enemies.

Now other of the Solarian ships were coming swiftly to the attack. Suddenly a combination of three of the ten-man cruisers stopped another of the great ships instantaneously. There was another soundless crash, and the giant mass of wreckage that heaped suddenly up glowed dully red from the energy of impact.

But now the little ships of the invaders got into action. They had been delayed by the desperate attempts of the dreadnaughts to wipe out their enemies with the death rays, and they could not cover the great distances without some delay.

When a battle spreads itself out through a ten-thousand mile cube of space—through a thousand billion cubic miles of space—it is impossible to cover it instantaneously with any machine.

Already nearly a hundred and fifty of the giant liners had gone into making that colossal mass of junk in space. They must protect the remaining cruisers! And it was that flight of small ships that did protect them. Many of the Solarians went down to death under their rays. The death rays were exceedingly effective, but the heat rays were not able to get quite as long a range, and they were easily detected by the invisibility locators, which meant certain destruction, for a molecular motion ray would be there in moments, once they had been located.

The main fleet of the Solar System was already on its way, and every moment drew closer to this running battle, for the great ships of the Nigrans had, although they were entering the system cautiously, been going at a very high speed, as interplanetary speeds are measured. The entire battle had been a running encounter between the two forces. The Solarian force, invisible because of its small size, was certainly getting the better of the encounter thus far, but now that the odds were changing, now that the small ships had come into the fray, engaging them at close range, they were not having so easy time of it.

It would be many hours before the full strength of the Solarian fleet could be brought to bear on the enemy. They were not able to retire and await their arrival, for they must delay the Nigran fleet. If even one of those great ships should safely reach the two planets behind them—!

But within a half hour of the original signal, the Rocket Squad had thrown itself into the battle with a fervor and abandon that has given that famous division a name that will last forever.

The small fliers of the Nigrans were beginning to take an appalling toll in the thinning ranks of the Solarians. The coming of the Rocket Squad was welcome indeed! They were able to maneuver as swiftly as the enemy; the speedsters were harder to spot than the Solarian ten-man and thirty-man boats. The Solarian speedsters were even smaller than the comparable Nigran craft, and some of these did a tremendous amount of damage. The heat ray was quite ineffective against the ten-man ships, even when working at full capacity, when produced by the small generators of the Nigran one-man boats. The cruisers could absorb the heat and turn it into power faster than the enemy could supply it. Beams from the monster interstellar liners were another matter, of course.

But the one-man speedsters had a truly deadly plan of attack against the liners. The plan was officially frowned upon because of the great risks the pilots must take. They directed their boats at one of the monster ships, all the power units on at full drive. As close to target as possible the man jumped from his ship, clothed, of course, in an altitude suit equipped with a radio transmitter and receiver.

Death rays could not stop the speedsters, and with their momentum, the invaders could not make it less deadly with their heat beam, for, molten, it was still effective. A projectile weighing twenty-two tons, moving a hundred miles a second, can destroy anything man can lift off a planet! Their very speed made it impossible to dodge them, and usually they found their mark. As for the risk, if the Solarian forces were victorious, the pilots could be picked up later, provided too long a time had not elapsed!

In the midst of the battle, the Solarians began to wonder why the Nigran fleet was decreasing so rapidly—certainly they had not caused all that damage! Then suddenly they found the answer. One of their ships—then another—and another fell victim to a pale red ray that showed up like a ghostly pillar of luminosity coming from nowhere and going nowhere! The answer? The invaders' ships were becoming invisible! The invisibility detectors were being overloaded now, and the hunt was hard, while the Nigrans were slipping past them and silently destroying Solarian ships! The molecular motion rays were quite effective on an invisible ship—once it had been found. They were destroying the Nigrans as rapidly as they were being destroyed, but they were letting some of them slip past! The luminous paint bombs and bullets were now called into play. All enemy ships were shot at with these missiles, and invisibility was forestalled.

At long last the dark bulk of the main fleet approached, a scarcely visible cloud of tiny darting metal ships. The battle so far had been a preliminary engagement. The huge ships of the Nigrans were forced to stop their attack, and releasing the last of the fliers, to retire to a distance, protected by a screen of small ships, for they were helpless against the Solarian speedsters. Invisibility fell into disfavor, too, now that there were plenty of Solarian ships, for the Nigrans were more conspicuous when invisible than when visible. The radio detector could pick them out at once.

The entire Nigran fleet was beginning to reveal the disorder and uncertainty that arose from desperation, for they were cornered in the most undesirable position possible. They were outside the Solarian fleet, and their ships were lighted by the glare of the sun. The defenders, on the other hand, were in such a position that the enemy could see only the "night" side of them—the shadowed side—and, as there was no air to diffuse the light, they were exceedingly hard to find. In the bargain, the radium paint was making life for the Nigrans a brief and flitting thing!

The invaders began to pay an awful toll in this their first real engagement. They lacked the necessary power to cover the entire Solarian fleet with their death rays, and their heat weapons were of little help. The power of the small ships did not count for much—and the big liners could not use their weapons effectively for their small fliers must be between them and their adversary. Despite this, however, the Nigrans so greatly outnumbered the Earth-Venus forces that it looked as though a long and costly war lay ahead.

At last the Solarian generals tried a ruse, a ruse they hoped would work on these beings; but they who never before had to plan a war in space, were not sure that their opponents had not had experience in the art. True, the Nigrans hadn't revealed any especially striking generalship—had, in fact, committed some inexcusable blunders—but they couldn't be sure. Though they didn't know it, the Solarians had the advantage of thousands of years of planetary warfare to rely on. This stood them in good stead now.

The Nigrans were rallying rapidly. To their surprise, the forces of the Solarians were dwindling, and no matter how desperately this remnant fought, they could not hold back the entire force of the Nigran fliers. At last it appeared certain that the small ships could completely engage the Solarian fleet!

Quickly the giant cruisers formed a great dense cone of attack, and at a given signal, the fliers cleared a hole for them through the great disc-shaped shield of the defenders. And with all their rays fanned out in a 100% overlap ahead of them, the Nigran fleet plunged through the disc of ships at close to four hundred miles per second. They broke through—were on their way to the unprotected planets!

The Solarian ships closed the gap behind them, and eighteen of the giant ships burst into wreckage as powerful beams found them, but for the most part the remnant of the defending forces were far too busy with the fliers to attack the large ships. Now, as the monster engines of destruction raced on toward the planets still approximately two billion miles away, they knew that, far behind them, their fliers were engaging the Solarians. They had left their guard—but the guard was keeping the enemy occupied while they were free to drive in!

Then from nowhere came the counterattack! Nearly five thousand thirty-man ships of Earth and Venus, invisible in the darkness of space, suddenly leaped into action as the dreadnoughts sped past. Their destroying rays played over the nigh-helpless giants, and the huge ships were crumbling into colossal derelicts. With the last of their guard stripped from them, they fell easy prey to the attackers. Faster than they could keep count they were losing their warships of space!

The ruse had worked perfectly! Nearly all of the ten-man and one-man ships had been left behind them in the original disc, while all the thirty-man light cruisers, and a few hundred each of the ten-man and one-man crafts sped away to form a great ring twenty thousand miles farther back. The Nigran fleet had flown blindly into the ambush.

There was only one thing left for them to do. They were defeated. They must return to their far-off black star and leave the Solarians in possession of their worlds. For all battle purposes their great force was nearly wiped out, only the fliers remained in force; and these could no longer be carried in the remnant of the great liners. Swiftly they fell back, passing again through the disc, losing thirty more vessels, then raced swiftly away from the fleet of their enemies.

The Solarians, however, were not content. Their ships were forming in a giant hollow cylinder, and as the sphere of the Nigrans retreated, their beams playing behind them, the cylinder moved forward until it surrounded them, and they raced together toward the distant lightless sun. The Solar end of the cylinder swiftly closed, blocked by a group of huge ships which had taken no visible part in the battle. The Nigrans had stopped using their rays; and the Solarians followed in armed readiness, not molesting as long as they were not molested.

Many days this strange flight lasted, till at last the great yellow sun, Sol, had faded in the distance to an unusually brilliant star. Then, suddenly visible out of the darkness, a strange black world loomed ahead, and the Nigran ships settled swiftly toward it. Through the airlocks the great liners settled to their planet. No action was taken so long as the Solarian ships were not menaced, but for eight long months the darting ships hung above the four englobed worlds of Nigra.

Then at last the astronomers of Earth and Venus sent through the billions of miles of ether their message of safety. The guard could return home, for the sun they had been guarding would soon be too far from Earth or Venus to make any attack logical. Despite this, for years to come the fleet would guard the rim of the System, just to be sure; but it appeared that the suns had passed, never again to meet.

A strange thing had happened during the passing of the stars. Pluto no longer circled Sol; it had been captured by Nigra! The great fleet returned to a changed Solar system. Sol was still at its center, but there were now ten planets, including two new ones that the sun had captured from Nigra in return for Pluto; and all the planets had shifted a bit in their orbits.

What the ultimate effect on the planets will be, we cannot say as yet. The change thus far is certainly not very great, though a somewhat warmer climate exists now on Earth, and it is a bit cooler on Venus. The long-range difference, however, will be exceedingly interesting.

The Solar System has just passed through an experience which is probably unique in all the history of the mighty nebula of which our sun is an infinitesimal part. The chances that one star, surrounded by a system of planets, should pass within a hundred billion miles of another star, similarly accompanied, was one in billions of billions. That both systems should have been inhabited by intelligent races—

It is easy to understand why the scientists could not believe Arcot's theory of attack from another sun until they had actually seen those other worlds.

In that war between two solar systems we learned much and lost much. Yet, in all probability we gained more than we lost, for those two new-old planets will mean tremendous things to us. Already scientists are at work in the vast museums and ancient laboratories that are on them, and every day new things are being discovered. We lost many men, but we saved our worlds, and we learned many invaluable secrets from the invaders. In addition, we have but scratched the surface of a science that is at least a thousand million years old!



EPILOGUE

Taj Lamor looked out across the void of space toward a fading point of yellow light. Far in the distance it glowed, and every second moved it many more miles farther from him. They had lost their struggle for life and a new sun, he had thought when he turned back, defeated, from that distant sun. But time had brought new hope.

They had lost many men in that struggle, and their dwindling resources had been strained to the limit, but now there was hope, for a new spirit had been born in their race. They had fought, and lost, but they had gained a spirit of adventure that had been dormant for millions of years.

Below him, in the great dim mass that was their city, he knew that many laboratories were in the full swing of active work. Knowledge and its application were being discovered and rediscovered. New uses were being found for old things, and their daily life was changing. It was again a race awake, rejuvenated by a change!

As the great sea of yellow fire that was that strange sun had faded behind their fleeing ships, leaving their dead planets still circling a dead sun, he had thought their last chance was gone forever. But hope had reawakened, with the birth of new ideas, new ways of doing things.

Tordos Gar had been right! They had lost—but in the losing, they had won!

Taj Lamor shifted his gaze to a blazing point of light, where a titanic sea of flame was burning with a brilliance and power that, despite the greater distance, made the remote yellow sun seem pale and dim. The blue-white glow told of a monster star, a star far brighter than the one they had just left. It had become the brightest star in their heavens. On their ancient star charts it was listed as a red giant, named Tongsil-239-e, which meant it was of the fifth magnitude and very distant. But in the long ages that had passed since it was classified, it had become a mighty sun—a star in its prime.

How were they to reach it? It was eight and one half light years away!

Their search for the force that would swing a world from its orbit had at last been successful. The knowledge had come too late to aid them in their fight for the yellow sun, but they might yet use it—they might even tear their planets from their orbits, and drive them as free bodies across the void. It would take ages to make the trip—but long ages had already passed as their dark planet swung through the void. What difference would it make if they were or were not accompanied by a dead star?

True, the star that was now their goal was a double star; their planets could not find orbits about it, but they might remedy that—they could tear one star free and hurl it into space, making the remaining sun suitable for their use.

But they would escape this dead sun.



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