When the First Interstellar War erupted, the pioneer fleets of Earth's
nations had barely pushed their explorations beyond the orbit of
Saturn. Except for the vessels of the International Meteor Guard,
spaceflight was still a military enterprise of America, Russia, England
and the other mega-powers.
During the first months the advantage lay wholly with the slim black
cruisers of the Enemy, who had an antigravity which allowed them
to hover near planets without going into orbit; and a frightening
degree of control over light itself. Indeed, their principal weapon
was a tight beam of visible light, a dense photonic stiletto with an
effective range of several Jupiter-diameters in vacuum. They also
used visible light, in the green band, for communication as men use
radio, sometimes broadcasting it and sometimes beaming it loosely in
strange abstract pictures that seemed part of their language. Their
gravity-immune ships moved by reaction to photonic jets the tightness
of which rendered them invisible except near the sun, where they tended
to ionize electronically dirty volumes of space. It was probably this
effective invisibility, based on light-control, which allowed them to
penetrate the Solar System as deep as Earth's orbit undetected, rather
than any power of travel in time or sub-space, as was first assumed.
Earthmen could only guess at the physical appearance of the Enemy,
since no prisoners were taken on either side.
Despite his impressive maneuverability and armament, the Enemy was
oddly timid about attacking live planets. He showed no fear of the big
gas planets, in fact hovering very close to their turgid surfaces, as
if having some way of fueling from them.
Near Terra the first tactic of the black cruisers, after destroying
Lunostrovok and Circumluna, was to hover behind the moon, as though
sharing its tide-lockedness--a circumstance that led to a sortie by
Earth's Combined Fleet, England and Sweden excepted.
At the wholly disastrous Battle of the Far Side, which was visible in
part to naked-eye viewers on Earth, the Combined Fleet was annihilated.
No Enemy ship was captured, boarded, or seriously damaged--except
for one which, apparently by a fluke, was struck by a fission-headed
anti-missile and proceeded after the blast to "burn," meaning that it
suffered a slow and puzzling disintegration, accompanied by a dazzling
rainbow display of visible radiation. This was before the "stupidity"
of the Enemy with regard to small atomic missiles was noted, or their
allergy to certain radio wave bands, and also before Terran telepaths
began to claim cloudy contact with Enemy minds.
Following Far Side, the Enemy burst into activity, harrying Terran
spacecraft as far as Mercury and Saturn, though still showing great
caution in maneuver and making no direct attacks on planets. It was as
if a race of heavily armed marine creatures should sink all ocean-going
ships or drive them to harbor, but make no assaults beyond the shore
line. For a full year Earth, though her groundside and satellite
rocketyards were furiously busy, had no vehicle in deep space--with one
exception.
* * * * *
At the onset of the War a fleet of five mobile bases of the U. S. Space
Force were in Orbit to Mercury, where it was intended they take up
satellite positions prior to the prospecting and mineral exploitation
of the small sun-blasted planet. These five ships, each with a skeleton
five-man crew, were essentially Ross-Smith space stations with a solar
drive, assembled in space and intended solely for space-to-space flight
inside Earth's orbit. A huge paraboloid mirror, its diameter four times
the length of the ship's hull, superheated at its focus the hydrogen
which was ejected as a plasma at high exhaust velocity. Each ship
likewise mounted versatile radio-radar equipment on dual lattice arms
and carried as ship's launch a two-man chemical fuel rocket adaptable
as a fusion-headed torpedo.
After Far Side, this "tin can" fleet was ordered to bypass Mercury
and, tacking on the sun, shape an orbit for Uranus, chiefly because
that remote planet, making its 84-year circuit of Sol, was currently
on the opposite side of the sun to the four inner planets and the two
nearer gas giants Jupiter and Saturn. In the empty regions of space the
relatively defenseless fleet might escape the attention of the Enemy.
However, while still accelerating into the sun for maximum boost, the
fleet received information that two Enemy cruisers were in pursuit. The
five ships cracked on all possible speed, drawing on the solar drive's
high efficiency near the sun and expending all their hydrogen and most
material capable of being vaporized, including some of the light-metal
hydrogen storage tanks--like an old steamer burning her cabin furniture
and the cabins themselves to win a race. Gradually the curving course
that would have taken years to reach the outer planet flattened into a
hyperbola that would make the journey in 200 days.
In the asteroid belt the pursuing cruisers turned aside to join in the
crucial Battle of the Trojans with Earth's largely new-built, more
heavily and wisely armed Combined Fleet--a battle that proved to be
only a prelude to the decisive Battle of Jupiter.
Meanwhile the five-ship fleet sped onward, its solar drive quite
useless in this twilight region even if it could have scraped together
the needed boilable ejectant mass to slow its flight. Weeks became
months. The ships were renamed for the planet they were aimed at. At
least the fleet's trajectory had been truly set.
Almost on collision course it neared Uranus, a mystery-cored ball
of frigid gas 32,000 miles wide coasting through space across the
fleet's course at a lazy four miles a second. At this time the fleet
was traveling at 100 miles a second. Beyond Uranus lay only the
interstellar night, into which the fleet would inevitably vanish....
* * * * *
Unless, Grunfeld told himself ... unless the fleet shed its velocity by
ramming the gaseous bulk of Uranus. This idea of atmospheric braking
on a grand scale had sounded possible at first suggestion, half a
year ago--a little like a man falling off a mountain or from a plane
and saving his life by dropping into a great thickness of feathery
new-fallen snow.
Supposing her solar jet worked out here and she had the reaction
mass, _Prospero_ could have shed her present velocity in five hours,
decelerating at a comfortable one G.
But allowing her 12,000 miles of straight-line travel through Uranus'
frigid soupy atmosphere--and that might be dipping very close to
the methane seas blanketing the planet's hypothetical mineral
core--_Prospero_ would have two minutes in which to shed her velocity.
Two minutes--at 150 Gs.
Men had stood 40 and 50 Gs for a fractional second.
But for two minutes.... Grunfeld told himself that the only surer way
to die would be to run into a section of the Enemy fleet. According to
one calculation the ship's skin would melt by heat of friction in 90
seconds, despite the low temperature of the abrading atmosphere.
The star Grunfeld had been waiting for touched the hazy rim of Uranus.
He drifted back to the eyepiece and began to follow it in as the pale
planet's hydrogen muted its diamond brilliance.