Boundary 2: Threshold (42 page)

The second good thing was that Europa had no atmosphere to speak of. This jury-rigged double ship had the aerodynamics of a falling bridge, and were there any atmosphere—even one as thin as Mars'—the pressure variations during reentry would probably rip them apart. Aside from the gravity well itself, she'd be able to treat the maneuvers as being the same as in deep space. That gave them a chance.
Not a great one . . . but I'd better make it good enough,
she thought.

"All right, everyone. We are almost there."

Europa now loomed before them, eclipsing even Jupiter in size as the combined
Munin/Nebula Storm
overtook it in its orbit at a differential of less than a kilometer per second. Smallest of the Galilean moons, it was still immense, half again as wide as Luna, far more massive, far more complex. From their current altitude, it looked as smooth and polished as a billiard ball, an ivory cueball with multiple browned lines like cracks from age covering its surface. Somewhere below that surface, Maddie knew—depending on the scientist you asked, anywhere between two and fifty kilometers below—there was a dark ocean that covered the entire moon to a depth ten times greater than the deepest parts of Earth's ocean.

The smoothness was deceptive. Europa might be the smoothest object in the solar system, but there were still plenty of ridges, blocks, edges, hills, and chasms, and they had only minimal control over their landing site. In the few hours they had, A.J. and Larry had gone over the available imagery and what they could make out with the onboard instruments and picked their best guess as to a landing trajectory that might offer decent landing topography . . . but it was still a crapshoot.

"About to begin maneuvers. I'm going to ask everyone to either cut out radios or stay quiet unless they have something I need to hear. This is going to take all my concentration, and I don't need even a gasp, a curse, or a prayer distracting me."

"Understood,"
A.J. acknowledged. She saw some people drop out of the network—mostly the former
Odin
crewmembers that she hadn't had time to get to know yet, and who weren't engineers involved in this maneuver. Helen and Larry also dropped out. Larry had done all he could, and Helen was not going to be able to do anything more, either, now that the gruntwork of putting the whole contraption together was over.

"Here goes . . ."

Munin
's rockets coughed and then began a low, rumbling roar at minimal power. She wanted—needed—to get a feel for the clumsy dual ship before she kicked in full power. It was sluggish . . . wobbly . . . still some imbalance . . . but there, A.J. and Horst's programming was kicking in, automatic compensation based on the accelerometers all over the ships. The departure from projected optimal course was minimal. "Working so far. Full de-orbit burn coming up in three, two, one . . ."

Now the rockets gave vent to full-bore thunder, sending a shudder of vibrations throughout
Nebula Storm
.
"Ice seal under stress . . . holding, but I'm seeing cracks starting to build. Think it will hold, but be ready,"
A.J. said quietly.

"Cables?"

"All well within limits. No shifting yet. The torque on the hab section connecting tubes and supports is getting awfully near their design limits, but doesn't seem to be increasing any more."

"Burn almost done . . . in five, four, three . . ."

Just as the
Munin
ceased its rumbling, there was a reverberating
crunch
. "What was that?"

"Ice seal shifted and broke. We're only held together with the string and duct tape now. On the positive side, we don't need to worry about making sure that part breaks when it comes to the time to separate."

"Any advice?"

Horst answered.
"When we do the other burn for landing preparation, begin very slowly, as before, then taper slowly. This will let any slack be taken up and stress the cables least. Backing down slowly will let the strain off the cables evenly—I hope—so there will be no great shifts."

"I understand." She leaned back. "It will be a while before we come to the landing decision. Larry, A.J., I want you to keep watch ahead of us and refine our landing site as much as possible. As we know from our little landing in
John Carter
, you don't have to hit at kilometers per second to ruin your day."

"We're on it. Take it easy for now."

She reached out and took Joe's hand. Even though the contact was just glove-to-glove, it felt good. "You okay?" he asked privately.

"Scared to death. I practiced a
lot
after that crash, and Bruce said I was getting pretty good, but I'm not half as good as he is, and I think he'd find this a hell of a challenge."

"You're my Supergirl. You'll do it."

She giggled. "Yeah, I'll just fly out and catch us if something goes wrong."

"I almost believe you could." He smiled at her fondly.

"I'd try, anyway."

"Maddie, all that matters is we're doing our best. And if anyone can get us down safe and sound, it's going to be you."

Once more his words made all the difference. She stopped worrying. If the worst happened, it happened.

It was no longer a moon. Europa was
down
, now; a planet of ice, of jumbled ridges, occasional craters, scattered blocks the size of
Odin
stuck in the center of smooth, featureless frozen white, all rolling by underneath them at a tremendous speed. "Without atmosphere, we're having to kill our speed directly. According to Larry and A.J., we will be landing near the area called the Conamara Chaos. There's no good way to predict smooth landing spots, if any, so we just have to wing it. Everyone make sure they are securely strapped in." She did not allow her voice to betray any uncertainty. Her review of the Conamara region didn't encourage her; "chaos" was a good description of the area, but outside of it wasn't much better. On a planetary scale, Europa was smooth; on a human scale, it was some of the most rugged-looking terrain she'd ever had to look at. Plenty of areas of Mars were smoother to land on. But . . . there were a few possibilities. If she could just get lined up right.

"Combined landing burn coming up."

The rocket came on again at minimal power, slowly building to maximum. Scraping noises and vibrations echoed through both ships as, despite the cables, the two shifted slightly with respect to each other. Horst and A.J.'s balancing application was strained to its limit, and Maddie could feel the combined ship moving toward some catastrophic adjustment that would send them spinning out of control. Instinctively she eased off on the thrust, watching the projections of time and velocity. She had to get their relative velocity with respect to Europa's surface down to less than a hundred meters per second. Five hundred meters per second, and descending. Altitude ten thousand meters. Four hundred meters per second. Something moved slightly, and the entire mass of strung-together high technology seemed to wobble in the sky before a combination of programmed adjustments and Maddie's gut-level instinct managed to damp it down. Three hundred meters per second, and they were below five thousand meters altitude. Ridges and many-meter-high scarps loomed below them, ice frozen metal-hard in vacuum at a temperature of one hundred sixty degrees below zero—more than two hundred and fifty below, in Fahrenheit. Two hundred meters per second and they were lower than she liked, but she had to take her time; A.J. and Horst both indicated silently, in messages on her VRD, that the cable links would shift if she went to full power again—shift and perhaps let go. One hundred fifty. Forty . . . thirty . . . twenty . . . One hundred ten . . . 

"One hundred meters per second relative.
Munin
, we are detaching from you. Horst, are you ready?"

"Ready to take controls. Good luck."

"Separation in five, four, three . . ."

Multiple demolition charges—specifically designed for vacuum use here in the outer system—detonated on cue, severing the cables at precisely selected locations.
Munin
peeled away from
Nebula Storm
with a very small burn from its lateral thrusters.

"
Munin
away. Retracting hab sections." The overloaded sections would slightly unbalance
Nebula Storm
, but she could use that to keep them oriented in what amounted to a "right side up" attitude when she did the braking burn. The automated balance application was adjusted to deal with the current situation; she could see A.J. watching it like a hawk.

"Altitude is about a thousand meters. Hold on, everyone. One way or another, we're almost done."

She cut off outside imagery for everyone but herself. No one else needed to see this, and right now it was not even vaguely comforting. A shattered chaos of icebergs hundreds of meters high, small but sharp-edged ridges running for kilometers, not a single smooth area larger than a football field in . . . 

Wait. What was that? She concentrated the imaging systems in that direction. Alongside that long, wider ridged valley . . . parallel to it, a wide, smooth area. And it might . . . barely . . . be in range.

She let a lateral jet bias them in that direction, saving the main engine's accumulators for the very end. The ground rose up . . . closer . . . closer . . . 

She couldn't restrain an intake of breath as the peak of a great block of ice passed
above
her. Above her and to the side, no more than sixty meters away. The terrain below her now was jagged, fangs of ice reaching for the ship. She had to clear them, but they were coming up to meet
Nebula Storm
.

The vague dark patch of smoothness was barely visible at this angle, but approaching. But she wouldn't make it. Unless . . . 

Another lateral burst, tilting them up. She fired a short, sharp pulse from the main engines, then fired the laterals to bring them back into the proper alignment. There was a faint jolt, but she maintained control, seeing that the very tail of
Nebula Storm
had clipped the top off one of the blocks of ice. But the ice was still rough below them, still clawing up—and then suddenly she saw darker ice, still no skating rink but not a mass of frozen teeth. She cut in the main engines. The accumulators dumped their hoarded power into the reaction mass, sent it roaring out the NERVA nozzle at many, many kilometers per second, making every gram of mass work to slow
Nebula Storm
.

Fifty . . . forty meters per second . . . Altitude eighteen meters . . . 

The rocket died off, power exhausted, with speed at five meters per second, altitude seven meters. A second or so later,
Nebula Storm
landed on Europa.

Munin
was trailing
Nebula Storm
, a considered choice based on wanting both vessels close together on Europa and knowing that
Nebula Storm
had neither the maneuverability nor design to control its landing. Horst and the others watched, almost holding their breaths.

"Almost down . . ." Horst breathed. Only a tiny bit more, and the ship would be down and still, as perfect a landing as could be imagined with such a vessel.

And then the
Nebula Storm
's rocket died.

Five meters per second sounded so slow—barely a brisk jog, nothing compared to the meteoric speeds the ship had possessed but a few days before. A man on Earth could easily have outrun it now. But the
Nebula Storm
massed nearly a thousand tons. This was no aircraft, but a solid mass the size of a patrol ship, a small runaway train. A plume of white dust and tumbling shards blasted from beneath the careening spaceship as the
Bemmius
-made hull carved a remorseless path through the ice of Europa. Ponderously, majestically, the great ship bounced, rear end coming up, front down to score another massive dashed line in the face of the Jovian moon, then rear end down again, both down, sliding, ripping through ice like the blade of a titanic ice-skate. The
Nebula Storm
skidded, turning slowly from end-on to broadside. One of the habitat extensions caught suddenly on a projecting ridge, crumpled, and tore free. The ship rolled slightly, trapping the connecting tube underneath its mass, shredding the composite and steel, steam erupting as the water inside boiled outward in vacuum, shrouding the careening vessel in white fog. To his horror, Horst saw, casting knife-edged shadows across the ice, a forty-meter ridge cutting across the relatively smooth ice like a wall, dead ahead of the out-of-control Ares-IRI vessel. He pointed, wordlessly.

"I see it. But the
Nebula Storm
, she is slowing . . ."

It takes immense force to stop a thousand mobile tons, and with only Europa's feeble gravity to provide the pressure, the
Nebula Storm
would not stop quickly. But stop it would, in the end, and already the five meters per second had become three and a half, three, cutting an interrupted gouge nearly a hundred meters wide across Europa in a stupendous fountain of crystalline white. Even as Horst began bringing
Munin
in for a landing, he could barely tear his eyes from the ponderous, deceptive grace of the
Nebula Storm
's slow-motion crash. He could hear someone praying in the background. "Stop, stop, God, please stop . . ."

Two and a half meters per second now, dropping, just a brisk walk—but there was no more room. Broadside on, the
Nebula Storm
smashed irresistibly into the immovable bulwark of steel-hard ice, sending a blast of steam, ice dust, and boulders of crystalline water spurting into the black sky of Europa. The cloud settled, unnaturally fast with no atmosphere to keep the dust suspended, and all was still. For a few seconds, no one said anything as Horst gave his full attention to bringing
Munin
to ground as close as possible to the crashed
Nebula Storm
. Only when he felt the huge lander settle with crushing solidity onto the ice did he speak. "
Nebula Storm
! Jackie, Helen, A.J.—are you all right?"

For a moment there was no answer, and he thought his heart might just stop. But then the voice of Madeline Fathom answered, as calm and collected as though she were sitting back on Earth.
"
Munin
, this is
Nebula Storm
. That probably looked worse than it was. We got a bit shaken up, but we are all fine. Joe's got a slight bruise on his forehead and Jackie got whacked across the shin by something that got loose in that last jolt, but her suit kept that from being anything serious. No leaks, all major systems still operating, and the hab unit we lost had the stuff in it we could most afford to lose. You can see that one of the others extended a little on impact, just over the top of this ridge, and it's twisted some, but Jackie doesn't think it's beyond repair."
Her image appeared on the screen, and they could all see the entire crew of
Nebula Storm
behind her.
"It's a good landing, because we're all going to walk away from it. And one day, we'll all be walking back into this ship and going home."