The Black Star Passes

by Jr. John W. Campbell

  V

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

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

  Each ship, both speedster and mother craft, was equipped with aninvisibility locator, a sensitive short-wave directional receiver, thatwould permit the operator to direct his rays at invisible targets. Theships themselves could not be made invisible, since they depended intheir very principle on the absorption of light-energy. If the walls ofevery part of the ship were perfectly transparent, they could absorb noenergy at all, and they would still be plainly visible--even more sothan before! They must remain visible, but they could also force theenemy to remain visible.

  Each ten-man ship carried an old-fashioned cannon that was equipped tohurl cannisters carrying the luminous paint. They decided that thesewould 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 inthe pilot room and at the observation posts. No light could escape. Toreduce the reflection to the absolute minimum, the ships had each beenpainted with a 99% absorptive black. In space they would be exceedinglydifficult targets.

  The heating effect of the sun on the black pigment when near the greatstar was rather disagreeably intense, and to cool the speedsters theyhad installed molecular director power units, which absorbed the heatand used the energy to drive the ship. Heaters offset the radiation lossof the black surface when too far from the sun.

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

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

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

  Arcot had gone to the conference held on Venus with the other men whohad investigated the great wrecks, and each scientist had related hisview of things and had offered suggestions. Arcot's idea of the blackstar 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 havecome from a great distance, and they agreed that they lived in anatmosphere of hydrogen, and judging from their pale skins, that theywere not used to the rays of a sun, they still insisted on the theory ofan outer planet of Sol.

  "You remember," explained Arcot, "several years ago there wasconsiderable discussion about the existence of a planet still furtherout from the sun than Pluto. It is well known that there are a number ofirregularities in the orbits of Neptune and Pluto that can't be causedby known planets, and an outer planet could have the necessary mass andorbit to account for them.

  "This attack from outer space was immediately taken as proof of thattheory, and it was very easily supported, too. My one good point thatstood for any length of time under their attacks was the fact that thoseships weren't developed in a year, nor a century, and that the chemicalconstitution of the men was so different. There were no new elementsdiscovered, except the light-matter, but they are rather wondering aboutthe great difference of earthly chemical constitution and theconstitution 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 actionon two passing suns.

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

  "But now their original velocity reasserts itself, and having spiraledabout each other for who can say how long--a year--a million yearsseems more probable--but still only an instant in the life of astar--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 nowthe gas will never fall back into the sun. Like some giant flaming cigarit reaches out into space and it will stay thus, for it has been set inrotation 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 developenergy from matter, for it was only the surface of the sun, and cool. Asit cools still further, there appear in it definite condensations, andthe beginnings of the planets are there. The great filament thatstretched from the sun to sun was cigar-shaped, and so the matter ismore plentiful toward the center, and larger planets develop. ThusJupiter and Saturn are far larger than any of the others. The two endsare tapering, thus Earth is larger than Venus, which is larger thanMercury, and Uranus and Neptune are both smaller than Saturn, Plutobeing smaller than either.

  "Mars and the asteroids are hard to explain. Perhaps it is easier tounderstand when we remember that the planets thus formed mustnecessarily have been rotating in eccentric orbits when they were firstborn, and these planets came too near the sun while gaseous, or nearlyso, and Mars lost much of its matter, while the other, which now existsonly as the asteroids, broke up.

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

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

  "But in order that it might happen, it requires that two stars passwithin the relatively short distance of a few billion miles of eachother. Space is not overcrowded with matter, you know. The density ofthe stars has been compared with twenty tennis balls roaming about8,000-mile sphere that the Earth fills up--twenty tennis balls in some270 billion cubic miles of space. Now imagine two of those tennisballs--with plenty of room to wander in--passing within a few yards ofeach other. The chances are about as good as the chances of two starspassing close enough to make planets.

  "Now let us consider another possibility.

  "The Black Star, as I told you, has planets. That means that it musthave thus passed close to another star. Now we have it coming close toanother sun that has been similarly afflicted. The chances of thathappening are inconceivably small. It is one chance in billions that theplanets will form. Two stars must pass close to each other, when theyhave all space to wander about in. Then those afflicted stars separate,and one of them passes close by a new star, which has thus beensimilarly afflicted with that one chance in billions--well, that is thena 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'msurprised they didn't, too--the explanation of the strange chemicalconstitution of these men of a solar system planet would not be soimpossible. It is quite possible that they live on a planet revolvingabout the sun which is, nevertheless, a planet of another star. It isquite conceivable to me that the chemical constitution of Neptune andPluto will be found to be quite different from that of the rest of ourplanets. The two filaments drawn out from the suns may not have mingled,though I think they did, but it is quite conceivable that, just beforeparting, our sun tore one planet, or even two or three, from the otherstar.

  "And that would explain these strange beings.

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

  "Ho--I wish they'd let me go on active duty with the space fleet! Ascientific reputation can be an awful handicap at times," he grinned. Hehad been rejected very emphatically when he had tried to enlist. TheInterplanetary governments had stated flatly that he was too importantas 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 asidefor the duration of the emergency. Space ships were being turned out attop speed, getting their fuel from the wrecks of the invaders' cruisers.Each ship needed only a small amount of the light-metal, for the energycontent was tremendous. And those ships had been gigantic.

  Already there was a fleet of speedsters and mother ships out there inspace, and with every passing hour others left the home planets, alwaysadding to the fighting force that was to engage the attackers deep inspace, where no stray ships might filter through to destroy the citiesof Earth or Venus. Assembly lines were now turning out ships so rapidlythat the training of their operators was the most serious problem. Thisdifficulty had finally been overcome by a very abbreviated trainingcourse 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 ofthe ordinary ships. One plant was devoted to making huge interstellarliners. These giants, made on Venus, were nearly a quarter of a milelong, and though diminutive in comparison with the giant Nigran ships,they were still decidedly large. Twelve of these could be completedwithin the next month, it was found; and one was immediately set asideas an officers' headquarters ship. It was recognized that the officersmust 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 thetransmission of reports.

  The ship must not be brought too near the front lest the officers beendangered and the entire engagement lost for want of the organizingcentral headquarters. The final solution had been the huge centralcontrol ship.

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

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

  The OX line was taken pointing toward one of the brightest of the fixedstars that was in the plane of the elliptic. The entire solar system wasthus marked off as had been the planets long ages before, into a systemof three dimensional latitude and longitude. This was imperative, inorder to assure the easy location of the point of first attack, and topermit the entire fleet to come into position there. A scattered guardwas to remain free, to avoid any false attacks and a later attack from apoint millions of miles distant. Earth and Venus were each equipped withgigantic 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 fearfultoll might be exacted from a vast city such as Chicago--with its thirtymillions! Or Karos, on Venus, with its fifteen and one half millions!

  The tension became greater and greater as with each passing day thepopulace of two worlds awaited the call from the far-flung guard. Themain bulk of the fleet had been concentrated in the center of theirgreat spherical shell of ships. They could only wait--and watch--andprepare! Hundreds of miles apart, yet near enough so that no shipexcept perhaps a one-man craft could pass them undetected; and behindthem were ships with delicate apparatus that could detect any foreignbody of any size whatever within a hundred thousand miles of them.

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