Where I Wasn't Going Part 3

Besides research, the big wheel would provide living quarters for men building other projects; would provide a permanent central for the network of communications beams that was gradually encompa.s.sing man's world and would eventually spread to the other planets as well.

Cooperating with this master communications central, other satellites, automatic so far, occupied the same orbit, leading and lagging by one hundred twenty degrees.

A twenty-four hour orbit would have been more advantageous from the point of view of communications, except for the interference that would have been occasioned by the vast flood of electrons encircling Earth in the outer Van Allen belt. These electrons, trapped by Earth's magnetic field from the solar wind of charged particles escaping the sun, unfortunately occupied the twenty-four hour orbit, and, as their orbit expanded and contracted under the influence of the shifting magnetic field and solar flares, could produce tremendous havoc even in automatic equipment, so that it had been deemed economically impractical to set up the originally-postulated three satellites in stationary twenty-four orbits as communications terminals.

As the next best choice, the thirty-six-hour orbit had been selected.

It gave a slow rate of angular displacement, since the satellite itself moved ten degrees an hour, while Earth moved 15, for a differential rate of only five degrees an hour, making fairly easy tracking for the various Earth terminals of the communications net; and making possible a leisurely view of more than ninety per cent of Earth's surface every seventy-two hours.

The other two power and communications stations which led and lagged s.p.a.ce Lab One by 120 each, would combine to command a complete view of Earth, lacking only a circle within the arctic regions, so that they could provide power and communications for the entire world--a fact which had been the political carrot which had united Earth in the effort to create the labs with their combined technologies.

The danger of such powerful instruments as Hot Rod, concentrating megawatt beams of solar energy for relay to earth, and which could also be one of man's greatest weapons if it fell into unscrupulous hands, had been carefully played down, and also carefully countered in the screening by the Security Forces of U.N. of the personnel board.

T minus three and counting.

On the zero signal Mike in the engineer's quarters would change the now idly-bubbling air jets in the rim-rivers over to the fully-directional drive jets necessary to spin the fluid in counter-rotation through the rim tanks.

The suiting-up and strapping down were probably unnecessary, Mike thought, but in s.p.a.ce you don't take chances.

"T minus two and counting." Bessie's voice rang over the com circuit in officially clipped clarity.

From the physics lab came a rather oddly pitched echo. "Allee allee in free fallee! Hold it, please, as Confusion would say! Paul forgot to secure the electrolite for the ECM equipment. Can't have these five-gallon bottles bouncing around!"

"And we can't have you bouncing around either, Dr. Chi Tung. Get that soup under wraps quick. How much time do you need?" came the captain's voice from his console angled over Bessie's head.

Clark's voice could be heard murmuring into his Earth-contact phone.

"T minus two. Holding."

Less than two minutes later, Dr. Chi released the hold by announcing briefly, "Machine shop and physics department secure."

"T minus two and counting...."

"T minus one and counting...." Bessie continued officially. "Fifty, forty, thirty, twenty...."

The faint whine of high-speed centrifugal compressors could be heard through the ship.

"Ten...." The jets that had previously bubbled almost inaudibly took on the sound of a percolating coffee pot.

"... Four, three, two, one, mark."

The bubbling became a hiss that settled into a soft susurrus of background noise, as the jets forced air through the river of water in the circular tanks of the rim.

The water began to move. By reaction, the wheel took up a slow, circular motion in the opposite direction.

Then, gently, the wheel shook itself and settled into a complacently off-center motion that placed Bessie somewhere near the actual center of rotation.

"We're out of balance, Mr. Blackhawk," said the captain, one hand on the intercom switch.

"Bessie, ask the Cow what's off balance." It was Mike's voice from engineering control. "Thought we had this thing trued up like a watch."

But the computer had already taken over, and was controlling the flow of water to the hydrostatic balance tank system, rapidly orienting the axis of spin against the true axis of the wheel.

The wobble became a wiggle; the wiggle became the slightest of sways; and under the computer's gentle ministrations, the sways disappeared and s.p.a.ce Lab One rolled true.

Slowly Mike inched the jet power up, and the speed and "gravity" of the rim rose--from 0.009 to 0.039 to the pre-scheduled 0.15 of a gravity--two RPM--at which she would remain until a thorough test schedule over several days had been accomplished. Later tests would put the rim through check-out tests to as high as 1.59 gee, but "normal" operation had been fixed at two RPM.

In the background, the susurrus of the air jets rose slightly to the soft lullaby-sound that the wheel would always sing as she rolled.

New, experimental, her full complement of six hundred scientists and service personnel so far represented by only one hundred sixty-three aboard, the big wheel that was s.p.a.ce Lab One rotated majestically at her hydrodynamically controlled two revolutions per minute.

She gave nearly half her ma.s.s to the water that spun her--huge rivers of water, pumped through the walls of the wheel's rim, forming a six-foot barrier between the laboratories within the rim and the cosmic and solar radiations of outer s.p.a.ce.

Arguments on Earth had raged for months over the necessities--or lack of them--for the huge ma.s.s of water aboard, but the fluid ma.s.s served many purposes better than anything else could serve those purposes.

As a radiation shield, it provided sufficient safety against cosmic radiations of s.p.a.ce and from solar radiations, except for solar flare conditions, to provide a margin of safety for the crew over the three months in which they would do their jobs before being rotated back to Earth for the fifteen-month recovery period.

The margin was nearly enough for permanent duty--and there were those who claimed it was sufficient--but the claim had not been substantiated, and the three months maximum for tour was mandatory.

Originally, shielding had not been considered of vital importance, but experience had proven the necessity. The first construction personnel had been driven back to Earth after two weeks, dosimeters in the red.

The third crew didn't make it. All five died of radiation exposure from a solar flare. An original two weeks' limit was raised as more shielding arrived--three weeks, four, five--now the shadowy edge of the theoretic ninety-day recovery rate from radiation damage and the ninety days required to get the maximum safe dosage overlapped--but safety procedures still dictated that a red dosimeter meant a quick return to Earth whether the rate of recovery overlapped or not.

[Ill.u.s.tration]

The question was still open whether more shielding would be brought up to make the overlap certain, or whether it would be best to maintain a personnel rotation policy indefinitely. Some factions on Earth seemed determined that rotation must remain not only a procedural but an actual requirement--their voices spoke plainly through the directives and edicts of U.N. Budget Control--but from what source behind this bureaucratic smokescreen it would have been difficult to say.

As a heat sink, the water provided stability of temperature that would have been difficult to achieve without it. Bathed in the tenuous solar atmosphere that extends well beyond the orbit of Earth, and with a temperature over 100,000 C, maintenance of a livable temperature on board the big wheel was not the straight-forward balancing of radiation intercepted/radiation outgoing that had been originally antic.i.p.ated by early writers on the subject.

True, the percentage of energy received by convection was small compared to that received by radiation; but it was also wildly variable.

As a biological cultural medium, the hydraulic system provided a basis for both air restoration and food supplies. When the proper balance of plankton and algae was achieved, the air jets that gave the ship its spin would also purify the ship's air, giving it back in a natural manner the oxygen it was now fed from tanks.

As a method of controlling and changing the rate of rotation of the wheel, the rivers of water had already proven themselves; and as a method of static balancing to compensate for off-center weights, ma.s.ses of it could be stopped and held in counterbalance tanks around the rim, thus a.s.suring that the observatory, in its stationary position on the hub, would not suddenly take up an oscillatory pattern of motion as the balance within the wheel was shifted either by moving equipment or personnel.

In effect, the entire ship operated against a zero-M-I calculation which could be handled effectively only by the computer. The moment of inertia of the ship must be constantly calculated against the moment of inertia of the hydraulic ma.s.s flowing in the rim. And the individual counterbalance tanks must constantly shift their load according to the motions of the crew and their ma.s.ses of equipment that were constantly being shifted during installation. For already the observatory was hard at work, and its time must not be stolen by inappropriate wobbles of the hub.

A continuously operating feedback monitor system was capable of maintaining accuracy to better than .01% both in the ma.s.s inertial field of centrifugal force affecting the rim; and in overall balance that might otherwise cause wobbles in the hub.

While such fine control would not be necessary to the individual comfort of the personnel aboard, it was very necessary to the accuracy of scientific observation, one major purpose of the lab; and even so, many of the experimenters would require continuous monitor observation from the computer to correct their observations against her instantaneous error curve.

The ma.s.s of water in the rim formed a sh.e.l.l six feet through, surrounding the laboratories and living quarters--walls, floor and ceiling--since its first function was that of radiation shielding.

But the bulk of this water was not a single unit. It was divided into separate streams, twenty in number, in each of which various biological reactions could be set up.

While a few of the rivers were in a nearly chemically pure state, most of them were already filling with the plankton and algae that would form the base of the major ecological experiments, some with fresh water as their medium, others using sea water, complete with its normal micro-organisms supplemented from the tanks of concentrate that Dr. Millie Williams had brought aboard. One or two of the rivers were operating on different cycles to convert human waste to usable forms so that it might reenter the cycles of food and air.