"Are you me?" a gentle voice asked.
"No," she said carefully. "I don't think so."
Vast astonishment. "You think you are not me?"
"Yes. I think so, anyway."
"Why?"
There didn't seem to be any proper response to that, so she went back to the beginning of the conversation and ran through it again, trying to bring it to another conclusion. Only to bump against that "Why?" once again.
"I don't know why," she said.
"Why not?"
"I don't know."
She looped through that same dream over and over again all the while that she slept.
When she awoke, it was raining again. This time, it was a drizzle of pure methane from the lower cloud deck at fifteen kilometers. These clouds were (the theory went) methane condensate from the wet air swept up from the sea. They fell on the mountains and washed them clean of tholin. It was the methane that eroded and shaped the ice, carving gullies and caves.
Titan had more kinds of rain than anywhere else in the Solar System.
The sea had crept closer while Lizzie slept. It now curled up to the horizon on either side like an enormous dark smile. Almost time now for her to begin her descent. While she checked her harness settings, she flicked on telemetry to see what the others were up to.
The robot turbot was still spiraling its way downward, through the lightless sea, seeking its distant floor. Consuelo was trudging through the tholin again, retracing her five-kilometer trek from the lander _Harry Stubbs_, and Alan was answering another set of webposts.
_"Modelos de la evolucion de Titanes indican que la luna formo de una nube circumplanetaria rica en amoniaco y metano, la cual al condensarse dio forma a Saturno asi como a otros satelites. Bajo estas condiciones en -- "_
"Uh ... guys?"
Alan stopped. "Damn it, O'Brien, now I've got to start all over again."
"Welcome back to the land of the living," Consuelo said. "You should check out the readings we're getting from the robofish. Lots of long-chain polymers, odd fractions ... tons of interesting stuff."
"Guys?"
This time her tone of voice registered with Alan. "What is it, O'Brien?"
"I think my harness is jammed."
Lizzie had never dreamed disaster could be such drudgery. First there were hours of back- and-forth with the NAFTASA engineers. What's the status of rope 14? Try tugging on rope 8. What do the D-rings look like? It was slow work because of the lag time for messages to be relayed to Earth and back. And Alan insisted on filling the silence with posts from the VoiceWeb. Her plight had gone global in minutes, and every unemployable loser on the planet had to log in with suggestions.
_"Thezgemoth337, here. It seems to me that if you had a gun and shot up through the balloon, it would maybe deflate and then you could get down."_
"I don't have a gun, shooting a hole in the balloon would cause it not to deflate but to rupture, I'm 800 hundred meters above the surface, there's a sea below me, and I'm in a suit that's not equipped for swimming. Next."
_"If you had a really big knife -- "_
"Cut! Jesus, Greene, is this the best you can find? Have you heard back from the organic chem guys yet?"
"Their preliminary analysis just came in," Alan said. "As best they can guess -- and I'm cutting through a lot of clutter here -- the rain you went through wasn't pure methane."
"No shit, Sherlock."
"They're assuming that whitish deposit you found on the rings and ropes is your culprit. They can't agree on what it is, but they think it underwent a chemical reaction with the material of your balloon and sealed the rip panel shut."
"I thought this was supposed to be a pretty nonreactive environment."
"It is. But your balloon runs off your suit's waste heat. The air in it is several degrees above the melting- point of ice. That's the equivalent of a blast furnace, here on Titan. Enough energy to run any number of amazing reactions. You haven't stopped tugging on the vent rope?"
"I'm tugging away right now. When one arm gets sore, I switch arms."
"Good girl. I know how tired you must be."
"Take a break from the voice-posts," Consuelo suggested, "and check out the results we're getting from the robofish. It's giving us some really interesting stuff."
So she did. And for a time it distracted her, just as they'd hoped. There was a lot more ethane and propane than their models had predicted, and surprisingly less methane. The mix of fractions was nothing like what she'd expected. She had learned just enough chemistry to guess at some of the implications of the data being generated, but not enough to put it all together. Still tugging at the ropes in the sequence uploaded by the engineers in Toronto, she scrolled up the chart of hydrocarbons dissolved in the lake.
Solute: Solute mole fraction
Ethyne: 4.0 x 10-4
Propyne: 4.4 x 10-5
1,3-Butadiyne: 7.7 x 10-7
Carbon Dioxide: 0.1 x 10-5
Methanenitrile: 5.7 x 10-6
But after a while, the experience of working hard and getting nowhere, combined with the tedium of floating farther and farther out over the featureless sea, began to drag on her. The columns of figures grew meaningless, then indistinct.
Propanenitrile: 6.0 x 10^-5
Propenenitrile: 9.9 x 10^-6
Propynenitrile: 5.3 x 10^-6
Hardly noticing she was doing so, she fell asleep.
She was in a lightless building, climbing flight after flight of stairs. There were other people with her, also climbing. They jostled against her as she ran up the stairs, flowing upward, passing her, not talking.
It was getting colder.
She had a distant memory of being in the furnace room down below. It was hot there, swelteringly so. Much cooler where she was now. Almost too cool. With every step she took, it got a little cooler still. She found herself slowing down. Now it was definitely too cold. Unpleasantly so. Her leg muscles ached. The air seemed to be thickening around her as well. She could barely move now.
This was, she realized, the natural consequence of moving away from the furnace. The higher up she got, the less heat there was to be had, and the less energy to be turned into motion. It all made perfect sense to her somehow.
Step. Pause.
Step. Longer pause.
Stop.
The people around her had slowed to a stop as well. A breeze colder than ice touched her, and without surprise, she knew that they had reached the top of the stairs and were standing upon the building's roof. It was as dark without as it had been within. She stared upward and saw nothing.
"Horizons. Absolutely baffling," somebody murmured beside her.
"Not once you get used to them," she replied.
"Up and down -- are these hierarchic values?"
"They don't have to be."