* * * * *
Unknowing of the storm, the _Empress of Kolain_ sped silently through
the void, accelerating constantly at one G. Hour after hour she was
adding to her velocity, building it up to a speed that would make the
trip in days, and not weeks. Her drivers flared dull red no more,
for there was no atmosphere for the ionic stream to excite. Her few
portholes sparkled with light, but they were nothing in comparison to
the starry curtain of the background.
Her hull was of a neutral color, and though the sun glanced from her
metal flanks, a reflection from a convex side is not productive of a
beam of light. It spreads according to the degree of convexity and is
lost.
What constitutes an apparent absence? The answer to that question is
the example of a ship in space flight. The _Empress of Kolain_ did
not radiate anything detectable in the electromagnetic scale from
ultralong waves to ultra-high frequencies; nothing at all that could be
detected at any distance beyond a few thousand miles. The sweep of her
meteor-spotting equipment would pass a spot in micro-micro-seconds at a
hundred miles; at the distance from Venus Equilateral the sweep of the
beam would be so fleeting that the best equipment ever known or made
would have no time to react, thus missing the signal.
Theorists claim a thing unexistent if it cannot be detected. The
_Empress of Kolain_ was invisible. It was undetectable to radio
waves. It was in space, so no physical wave could be transmitted to
be depicted as sound. Its mass was inconsiderable. Its size as cosmic
sizes go was comparatively sub-microscopic, and therefore it would
occult few, if any, stars. Therefore, to all intents and purposes, the
_Empress of Kolain_ was non-existent, and would remain in that state
of material-non-being until it came to life again upon its landing at
Venus.
Yet the _Empress of Kolain_ existed in the minds of the men who were
to find her. Like the shot unseen, fired from a distant cannon, the
_Empress of Kolain_ was coming at them with ever-mounting velocity, its
unseen course a theoretical curve.
And the ship, like the projectile, would land if the men who knew of
her failed in their purpose.
* * * * *
Don Channing and Walt Franks found their man in the combined dining
room and bar--the only one in sixty million miles. They surrounded him,
ordered a sandwich and beer, and began to tell him their troubles.
Charles Thomas listened for about three minutes. "Boy," he grinned,
"being up in that shiny, plush-lined office has sure done plenty to
your think-tank, Don."
Channing stopped talking. "Proceed," he said. "In what way has my
perspective been warped?"
"You talk like Burbank," said Thomas, mentioning a sore spot of some
months past. "You think a mass detector would work at this distance?
Nuts, fellow. It might, if there were nothing else in the place to
interfere. But you want to shoot out near Mars. Mars is on the other
side of the Sun--and Evening Star to anyone on Terra. You want us to
shoot a slap-happy beam like a mass detector out past Sol; and then a
hundred and forty million miles beyond in the faint hope that you can
triangulate upon a little mite of matter; a stinking six hundred-odd
feet of aluminum hull mostly filled with air and some machinery and
so on. Brother, what do you think all the rest of the planets will do
to your piddling little beam? Retract, or perhaps abrogate the law of
universal gravitation?"
"Crushed," said Franks with a sorry attempt at a smile.
"_Phew!_" agreed Channing. "Maybe I should know more about mass
detectors."
"Forget it," said Thomas. "The only thing that mass detectors are any
good for is to conjure up beautiful bubble dreams, which anyone who
knows about 'em can break with the cold point of icy logic."
"What would you do?" asked Channing.
"Darned if I know. We might flash 'em with a big mirror--if we had a
big mirror and they weren't heading into the Sun."
"Let's see," said Franks, making tabulations on the tablecloth.
"They're a couple of hundred million miles away. In order that your
mirror present a recognizable disk, it should be about twice the
diameter of Venus as seen from Terra. That's eight thousand miles
in--at the least visibility--say, eighty million or a thousand-to-one
ratio. The _Empress of Kolain_ is heading at us from some two hundred
million miles, so at a thousand-to-one ratio our mirror would have to
be twenty thousand miles across. Some mirror!"
Don tipped Walt's beer over the edge of the table, and while the other
man was busy mopping up and muttering unprintables, Don said to Thomas:
"This is serious and it isn't. Nobody's going to lose their skin if we
don't, but a problem has been put to us and we're going to crack it if
we have to skin our teeth to do it."
"You can't calculate their position?"
"Sure. Within a couple of hundred thousand miles we can. That isn't
close enough."
"No, it isn't," agreed Chuck.
Silence fell for a moment. It was broken by Arden, who came in waving
a telegram. She sat down and appropriated Channing's glass, which
had not been touched. Don opened the sheet and read: "Have received
confirmation of your effort. I repeat, spare no expense!" It was
signed: "Keg Johnson, Interplanet."
"Does that letter offer mean anything to you?" asked Arden.
"Sure," agreed Don. "But at the same time we're stumped. Should we be
doing anything?"
"Anything, I should think, would be better than what you're doing at
present. Or does that dinner-and-beer come under 'expenses'?"
Arden stood up, tossed Channing's napkin at him, and started toward
the door. Channing watched her go, his hand making motions on the
tablecloth. His eyes fell to the table and he took Franks' pencil and
drew a long curve from a spot of gravy on one side of the table to a
touch of coffee stain on the other. The curve went through a bit of
grape jelly near the first stain.
"Here goes the tablecloth strategist," said Franks. "What now, little
man?"
"That spot of gravy," explained Don, "is Mars. The jelly is the
_Empress of Kolain_. Coffee stain is Venus, and up here by this
cigarette burn is Venus Equilateral. Get me?"
"Yop, that's clear enough."
"Now it would be the job for seventeen astronomers for nine weeks to
predict the movements of this jelly spot with respect to the usual
astral standards. But, fellows, we know the acceleration of the
_Empress of Kolain_, and we know her position with respect to Mars at
the instant of take-off. We can correct for Mars' advance along her--or
his--orbit. We can figure the position of the _Empress of Kolain_ from
her angular distance from Mars! That's the only thing we need know. We
don't give a ten-dollar damn about her true position."
Channing began to write equations on the tablecloth. "You see, they
aren't moving so fast in respect to us. The course is foreshortened as
they are coming almost in line with Venus Equilateral, curving outward
and away from the Sun. Her course, as we see it from the station here,
will be a long radius-upward curve, slightly on the parabolic side.
Like all long-range cruises the _Empress of Kolain_ will hoist herself
slightly above the plane of the ecliptic to avoid the swarm of meteors
that follow about the Sun in the same plane as the planets, lifting the
highest at the point of greatest velocity.
"I get it," said Franks. "We get the best beam controller we have to
keep the planet on the cross hairs. We apply a spiral cam to advance
the beam along the orbit. Right?"
"Right." Don sketched a conical section on the tablecloth and added
dimensions. He checked his dimensions against the long string of
equations, and nodded. "We'll drive this cockeyed-looking cam with an
isochronic clock, and then squirt a beam out there. Thank the Lord for
the way our beam transmitters work."
"You mean the effect of reflected waves?" asked Chuck.
"Sure," grinned Don. "There's plenty of radar operating at our
transmitting frequencies or near by. So far, no one has ever tried
to radar anything as small as a spacecraft at that distance, though
getting a radar signal from a planet is duck soup. Yet," he reflected
cheerfully, "there are a couple of things we have handy out here, and
one of them is a plethora of power output. We can soup up one of our
beam transmitters and use it with a tightened beam to get a radar fix
off of the _Empress of Kolain_."
"And then?" asked Franks.
"Then we will have left the small end, which I'll give to you, Walt, so
that you can have part of the credit."
Walt shook his head. "The easy part," he said uncheerfully. "By which
you mean the manner in which we contact them and make them listen to
us?"
"That's her," said Don with a cheerful smile.
"Fine," said Thomas. "Now what do we do?"
"Clear up this mess so we can make the cam. This drawing will do, just
grab the tablecloth."
Joe, the operator of Venus Equilateral's one and only establishment
for the benefit of the stomach, came up as the three men began to move
their glasses and dishes over to an empty table. "What makes with
the tablecloth?" he asked. "Want a piece of carbon paper and another
tablecloth?"
"No," said Don nonchalantly. "This single copy will do."
"We lose lots of tablecloths that way," said Joe. "It's tough, running
a restaurant on Venus Equilateral. I tried using paper ones once, but
that didn't work. I had 'em printed but when the solar system was on
'em, you fellows drew schematic diagrams for a new coupler circuit. I
put all kinds of radio circuits on them, and the gang drew plans for
antenna arrays. I gave up and put pads of paper on each table, and the
boys used them to make folded paper airplanes and they shot them all
over the place. Why don't you guys grow up?"
"Cheer up, Joe. But if this tablecloth won't run through the blueprint
machine, we'll squawk!"
Joe looked downcast, and Franks hurried to explain: "It isn't that bad,
Joe. We won't try it. We just want to have these figures so we won't
have to run through the math again. We'll return the cloth."
"Yeah," said Joe at their retreating figures. "And for the rest of its
usefulness it will be full of curves, drawings, and a complete set of
astrogating equations." He shrugged his shoulders and went for a new
tablecloth.
Don, Walt and Chuck took their improvised drawing to the machine shop,
where they put it in the hands of the master mechanic.
"This thing has a top requirement," Don told him. "Make it as quick as
you can."
Master Mechanic Warren took the cloth and said: "You forgot the note.
You know, 'Work to dimensions shown, do not scale this drawing.' Lord,
Don, this silly looking cam will take a man about six hours to do.
It'll have to be right on the button all over, no tolerance. I'll have
to cut it to the 'T' and then lap it smooth with polishing compound.
Then what'll you test it on?"
"Sodium light interferometer. Can you do it in four hours?"
"If nothing goes wrong. Brass all right?"
"Anything you say. It'll only be used once. Anything of sufficient
hardness for a single usage will do."
"I'll use brass then. Or free-cutting steel may be better. If you make
it soft you have the chance of cutting too much off with your lapping
compound. We'll take care of it, Don. The rest of this stuff isn't too
hard. Your framework and so on can be whittled out and pasted together
from standard girders, right?"
"Sure. Plaster them together any way you can. And we don't want them
painted. As long as she works, phooey to the looks."
"Fine," said Warren. "I'll have the whole business installed in the
Beam Control Room in nine hours. Complete and ready to work."
"That nine hours is a minimum?"
"Absolutely. After we cut and polish that screwball cam, we'll have to
check it, and then you'll have to check it. Then the silly thing will
have to be installed and its concentricity must be checked to the last
wave length of cadmium light. That'll take us a couple of hours, I
bet. The rest of the works will be ready, checked, and waiting for the
ding-busted cam."
"Yeah," agreed Franks. "Then we'll have to get up there with our works
and put the electricals on the mechanicals. My guess, Don, is a good,
healthy twelve hours before we can begin to squirt our signal."
* * * * *
Twelve hours is not much in the life of a man; it is less in the life
of a planet. The Terran Standard of Gravity is so small that it is
expressed in feet per second. But when the two are coupled together as
a measure of travel, and the standard Terran G is applied for twelve
hours steady, it builds up to almost three hundred miles per second,
and by the end of that twelve hours, six million miles have fled into
the past.
Now take a look at Mars. It is a small, red mote in the sky, its
diameter some four thousand miles. Sol is eight hundred thousand
miles in diameter. Six million miles from Mars, then, can be crudely
expressed by visualizing a point eight times the diameter of the Sun
away from Mars, and you have the distance that the _Empress of Kolain_
had come from Mars.
But the ship was heading in at an angle, and the six million miles did
not subtend the above arc. From Venus Equilateral, the position of the
_Empress of Kolain_ was more like two diameters of the Sun away from
Mars, slightly to the north, and on the side away from Sol.
It may sound like a problem for the distant future, this pointing
a radio beam at a planet, but it is no different from Galileo's
attempts to see Jupiter through his Optik Glass. Of course, it has had
refinements that have enabled man to make several hundred hours of
exposure of a star on a photographic plate. So if men can maintain a
telescope on a star, night after night, to build up a faint image, they
can also maintain a beamed transmission wave on a planet.
All you need is a place to stand; a firm, immobile platform. The
three-mile-long, one-mile-diameter mass of Venus Equilateral offered
such a platform. It rotated smoothly, and upon its "business" end a
hardened and highly polished set of rails maintained projectors that
were pointed at the planets. These were parabolic reflectors that
focussed ultra-high-frequency waves into tight beams which were hurled
at Mars, Terra, and Venus for communication.
And because the beams were acted upon by all of the trivia in the Solar
System, highly trained technicians stood their tricks at the beam
controls. In fifty million miles, even the bending of electromagnetic
waves by the Sun's mass had to be considered. Sunspots made known
their presence. And the vagaries of land transmission were present in
a hundred ways due to the distance and the necessity of concentrating
every milliwatt of available power on the target.
This problem of the _Empress of Kolain_ was different. Spaceships were
invisible, therefore the beam-control man must sight on Mars and the
mechanical cam would keep the ship in sight of the beam.
The hours went past in a peculiar mixture of speed and slowness. On one
hand the minutes sped by swiftly and fleetingly, each tick of the clock
adding to the lost moments, never to be regained. Time, being precious,
seemed to slip through their fingers like sifting sand.
On the other hand, the time that must be spent in preparation of the
equipment went slow. Always it was in the future, that time when their
experiment must either prove a success or a failure. Always there was
another hour of preparatory work before the parabolic reflector was
mounted; and then another hour before it swung freely and perfectly
in its new mounting. Then the minutes were spent in anticipation of
the instant that the power stage of transmitter was tested and the
megawatts of ultra-high-frequency energy poured into the single rod
that acted as a radiator.
It was a singularly disappointing sight. The rod glowed not, and the
reflector was the same as it was before the rod drew power. But the
meters read and the generators moaned, and the pyrometers in the
insulators mounted as the small quantity of energy lost was converted
into heat. So the rod drew power, and the parabolic reflector beamed
that power into a tight beam and hurled it out on a die-true line.
Invisible power that could be used in communications.
Then the cam was installed. The time went by even slower then, because
the cam must be lapped and polished to absolute perfection, not only of
its own surface but to absolute concentricity to the shaft on which it
turned.
But eventually the job was finished, and the men stood back, their eyes
expectantly upon Don Channing and Walt Franks.
Don spoke to the man chosen to control the beam. "You can start any
time now. Keep her knifed clean, if you can."
The man grinned at Channing. "If the devils that roam the void are with
us we'll have no trouble. We should all pray for a phrase used by some
characters in a magazine I read once: 'Clear ether!' We could use some
right now."
He applied his eyes to the telescope. He fiddled with the verniers
for a brief time, made a major adjustment on a larger handwheel, and
then said, without removing his eye from the 'scope, "That's it, Dr.
Channing."
Don answered: "O.K., Jim, but you can use the screen now. We aren't
going to make you squint through that pipe for the next few hours
straight."
"That's all right. I'll use the screen as soon as you can prove we're
right. Ready?"
"Ready," said Channing.
Franks closed a tiny switch. Below, in the transmitter room, relays
clicked and heavy-duty contacts closed with blue fire. Meters began
to climb upward across their scales, and the generators moaned in a
descending whine. A shielded monitor began to glow, indicating that
full power was vomiting from the mouth of the reflector.
And out from the projector there went, like a spear-head, a wave-front
of circularly polarized microwaves. Die-true they sped, crossing the
void like a line of sight to an invisible spot above Mars and to the
left. Out past the Sun, where they bent inward just enough to make
Jim's job tough. Out across the open sky they sped at the velocity of
light, and taking sixteen minutes to get there.