Another couple of thousand feet higher, Benacerraf called a halt. She felt hot and cooped up in her suit. She felt as if she could just open up her faceplate, take a deep breath of this cool mountain air, and rub a little snow in her face.

Angel slowed and stopped. Over the VHP link between them she could hear the rattle of his vacuum-damaged throat, the slurping of water from the nipple in his helmet. Discreetly, Benacerraf checked his suit diagnostics on her chest panel. He was using a lot of consumables, but no more than she was.

“What do you think?” he said at length. “Is the regolith deep enough here?”

“It’s hard to tell. It all feels the same underfoot.”

“The depth is probably pretty uniform, away from the gumbo layer,” Rosenberg said from Tartarus. “It’s just, the higher you go, the cleaner it should get.”

“This will do as well as anywhere,” Benacerraf said. “Come on, Bill. Let’s get these damn sleds filled up.”

She bounded down the few paces to the side of her sled and lifted out her shovel.

As it happened, the shovel was the same piece of equipment she’d used to bury Nicola Mott.

Using both hands, holding the handle away from her body, she pushed the rounded edge of the shovel blade into the regolith. There was a hiss of metal against ice grains.

The blade sank in easily for a few inches, but resistance built up quickly. When the blade was maybe five inches deep, she couldn’t push it any further in. She hopped forward and leaned over the crude handle of the shovel, propping it under her belly with her hands still wrapped around it, trying to use her weight to push the shovel deeper.

She achieved maybe another inch of penetration. In this gravity, her weight didn’t count for a lot.

She straightened up, panting, and lifted up the shovel. Some of the ice she’d raised so laboriously just floated off the blade.

She swivelled to the sled, and dumped in the ice regolith. It fell slowly, and rattled as it hit the aluminum hull of the sled.

She straightened up again. “It’s not going to be easy,” she said to Rosenberg, “When you push in the blade, the regolith compacts after a couple of inches. It feels more like sand than snow—”

“It isn’t snow,” Rosenberg said.

“Whatever. It’s going to take a long time to fill the sleds like this.”

“Paula.” Bill Angel said. Try this.”

She turned to look.

He was bending, closer to the ground, so that his blade was entering the regolith almost parallel to the surface. “See?” he said. It slides easy into these looser top layers. Then you can scoop up a big shovelful. I can feel it.” He was right, she saw; he was managing to lift big, tottering heaps of the regolith, which he dumped into his sled.

“I guess he’s right,” Rosenberg said. “You’re gathering raw materials for life support, Paula, not digging for a core sample. Get it whichever way is easiest.”

She bent, and started scraping up the regolith the way Angel did it. The first couple of times she managed to come away with piles of loosely-packed regolith on her blade as big and precarious as Angel’s. But the constant bending and straightening, against the stiffness of her suit, began to tell on her lower back and thighs.

She turned so that she was working uphill. That brought the regolith closer, and made it a little easier on her back, but it was still difficult, heavy work. Her EMU wasn’t made for heavy labor; it was hot, confining, uncomfortable, and she wished again she could take it off.

She thought about Angel. Now he was humming, the same marching tune as before.

Perhaps it was the climb. She felt vaguely exhilarated herself — liberated by the steady exercise, the sense of altitude, the crispness of the icy regolith.

She realized now that she’d never truly gotten over her sense of confinement after being cooped up in Discovery for all those years; Titan, with its lousy visibility, socked-in clouds and gloopy, impeding surface, wasn’t much of a release.

Maybe the same factors are working on Angel, she thought. Maybe this is working to clear out the contents of his head.

All he needed, she supposed, was a little space.

The light changed, subtly. It became somehow pearly.

She lifted up her head.

Raindrops were falling towards her face.

It wasn’t like rain on Earth.

It was methane rain.

The biggest drops were blobs of liquid a half-inch across. They came down surrounded by a mist, of much smaller drops. The drops fell slowly, perhaps five or six feet in a second. It was more like being caught in a snowstorm, with the flakes replaced by these big globules of methane liquid. The drops weren’t spheres; they were visibly deformed into flat hockey-puck shapes, flattened out, she supposed, by air resistance. They caught the murky light, shimmering.

The first drops hit her visor.

Each drop impacted with a fat, liquid noise; their splash was slow and languid. The drops spread out rapidly, or else collapsed into many smaller, more compact droplets over the plexiglass. Low surface tension, she thought automatically. Some of the liquid trickled down the contours of her visor, but the evaporation of the drops, over such a large area, was rapid, and each drop dried quickly.

Her face felt a little cooler, she guessed because of the evaporation of the liquid, carrying away some of her heat.

She leaned forward, compensating for the mass of her pack, and looked down. As it hit the ground, each raindrop broke up into many smaller drops, which trickled rapidly into the regolith, rinsing the tholin streaks off the ice.

Bill Angel turned his head this way and that, letting the rain fall over his faceplate and helmet. “It sounds beautiful,” he said. “Like being a kid again. Lying under a wooden roof at night, hearing the rain come down…”

“Yes,” she said. “Yes.” And in that moment she felt doser to Angel than at any time since they left Earth.

“You know,” Rosenberg said, “of all the worlds in the Solar System, only Earth and Titan know rain. I wish I was there.”

“Next time, Rosenberg.”

She stood in the rain, wishing it would go on forever. Not for the first time she was lulled into a kind of peace by the slowness of Titan, the paradoxical heaviness of time in this thin gravity, the slow rhythms of nature here; it was as if she was shedding the frantic, energy-laden pace of Earth, and becoming a creature of Saturn twilight.

At last, the slow patter of drops against her helmet stopped. She felt a sharp stab of regret.

There was still a faint wash of small droplets around her, but these were dissipating quickly. And now there was a mist in the air, a light, yellowish fog; it made the air seem brighter, like the air after a storm on Earth. Angel, standing before her, looked as if he had some kind of halo around him.

She reported all this to Rosenberg.

“That’s a rain ghost, Paula. I want you to take a sample…”

She dug a sample bottle out of a pocket on her EMU, and opened it to the air. “Why?”

“The rain starts by nucleating around particles in the upper atmosphere. That stuff is usually suspended higher up, and won’t reach the surface. But it can be transported down by the weight of the rain, down to lower altitudes. When the rain stops, the last drops evaporate, leaving their cores exposed. The rain ghost. You see? Paula, what we have is a free sample of upper-altitude haze particles.”

“Terrific.” She stoppered the bottle, labelled it with her propelling pencil (not a pen — ink froze), and put the bottle back in her pocket.

She looked around. The rain had gone: evaporated from her visor, and was absorbed into the ground. Above them, the methane clouds, evidently rained out, had cleared to a scattered, broken layer of dark fragments, revealing an orange glow above.