But Nemoto, of course, had not yet heard her question. “…A captured asteroid, perhaps? That would explain the orbit. But its shape appears too regular. And the cratering is limited. How old? Less than a billion years, more than five hundred million. And there is an anomaly with the density. Therefore… Ah. But what is necessity? You have a fat reserve of fuel, Carole, even now — more than enough to bring you home. And we are here not for pure science, but to investigate anomalies. Look at this thing, Carole. This object is too small, too symmetrical to be natural. And its density is so low it must be hollow.

“Carole, this is an artifact. And it has been here, orbiting Venus, for hundreds of millions of years. That is its significance.”

She held her hands out before the approaching moonlet.

There was no discernible gravity. It was not like jumping down to the surface of a world, but more like drifting toward a dark, dusty wall.

When her gloves impacted, a thin layer of dust compressed under her fingertips. The gentle pressure was sufficient to slow her, and then she found a layer of hard rock beneath. Grains billowed up around her hands, sparkling. Some of them clung to her gloves, immediately streaking their silvery cleanliness, and some drifted away, unrestrained by this odd moonlet’s tenuous gravity.

It was an oddly moving moment. I’ve come a hundred million kilometers, she thought. All that emptiness. And now I’ve arrived. I’m touching this lump of debris. Perhaps all travelers feel like this, she mused.

Time to get to work, Carole.

She took a piton from her belt. She had hastily improvised it from framing bolts on the ship. With a geology hammer intended for Venus, she pounded at the spike. Then she clipped a tether line to the piton.

“It looks like moondust,” she reported to distant Nemoto. She scooped up a dust sample and passed it through a portable lab unit for a quick analysis. Then she held the lab over the bare, exposed rock and let its glinting laser beam vaporize a small patch, to see if the colors of the resulting rock mist might betray its nature.

Then, spike by spike, she began to lay a line from her anchor point, working across the folds and ridges of this battered, tightly curved miniature landscape, toward the pole of the moonlet. There, Nemoto said she had detected what appeared to be a dimple, a crater too deep for its width: it was an anomaly, here on this anomalous moon.

Nemoto, reacting to her first observations and images, began to whisper in her ear, a remote insect. “Lunar regolith, yes. And that rock is very much like lunar highlands material: basically plagioclase feldspar, a calcium-aluminum silicate. Carole, this appears to be a bubble of lunar-type rock — a piece of a larger body, a true Venusian moon, perhaps? — presumably dug out, melted, shaped, thrown into orbit… But why? And why such a wide, looping trajectory?…”

She kept talking, speculating, theorizing. Carole tuned her out. After all, in a few more minutes, she would know.

She had reached the dimple. It was a crater perhaps two meters across — but whereas most of the craters here, gouged out by impacts, were neat, shallow saucers, this one was much deeper than its width — four, five meters perhaps.

Almost cylindrical.

She found her heart hammering as she clambered into this pit of ancient darkness; a superstitious fear engulfed her.

With brisk motions, she fixed a small radio relay box to the lip of the dimple. Then she stretched a thin layer of gas-trapping translucent plastic over the dimple. Of course by doing this she was walling herself up inside this hole in the ground. It was illogical, but she made sure she could punch out through that plastic sheet before she finished fixing it in place.

She saw something move in the sky above. She gasped and stumbled, throwing up a spray of dust.

A flower-ship cruised by, its electromagnetic petals folded, jewel-like Gaijin patrolling its ropy flanks.

She scowled up. “I want company,” she said. “But you don’t count.”

She turned away and let herself drift down to the bottom of the pit.

She landed feetfirst. The floor of the pit felt solid, a layer of rock. But the dust was thicker here, presumably trapped by the pit. When she looked up she saw a circle of stars framed by black, occluded by a little spectral distortion from the plastic.

Nothing happened. If she’d expected this “door” to open on contact, she was disappointed.

But Nemoto wasn’t surprised. “This artifact — if that’s what it is — may predate the first mammals, Carole. You wouldn’t expect complex equipment to keep functioning so long, would you? But there must be a backup mechanism. And I’ll wager that is still working.”

So Carole got to her hands and knees, trying to keep from pushing herself away from the ground, and she scrabbled in the dirt, her gloved hands soon filthy.

She found a dent.

It was maybe half a meter across. There was a bar across the middle of it. The bar was held away from the lower surface, and was fixed by a kind of hinge mechanism at one end.

Once more her heart hammered, and she felt a pulse in her forehead. Up to now, there had been nothing that could have proven, unambiguously, Nemoto’s assertion that the moonlet was an artifact. But there was surely no imaginable natural process by which a moon could grow a lever, complete with hinge.

She wrapped both hands around the lever and pulled.

Nothing happened. The lever felt immovable, as if it was welded tight to the rocky moon — as, of course, it might be, after all this time.

She braced herself with a piton hammered into the “door,” and pushed. Nothing. She twisted the lever clockwise, without success.

Then she twisted it counterclockwise.

The lever turned smoothly. She felt the click of buried, heavy machinery — bolts withdrawing, perhaps. The floor fell away beneath her.

Quickly she let go of the lever. She was left floating, surrounded by dust, suspended over a pit of darkness. Some kind of vapor sparkled out around her.

Making sure her pitons were secure, she slid past walls of rock and through the open door.

Nemoto’s recruitment pitch had been simple. “The flight will make you rich,” she’d promised.

Carole had been skeptical. After all, she was only going as far as Venus, a walk around the block compared to the light-years-long journeys undergone by the handful of interstellar travellers who had followed Reid Malenfant through the great Saddle Point gateways — even if, twenty years after the departure of Madeleine Meacher, the first, none of them had yet returned.

But still, Nemoto turned out to be right. Nemoto’s subtle defiance of the Gaijin’s unstated embargo on Venus had evidently struck a chord, and Carole’s shallow fame had indeed led to lucrative opportunities she hadn’t been ashamed to exploit.

But it wasn’t the money that had persuaded Carole to commit three years of her life to this unlikely jaunt.

“Think of your mother,” Nemoto had whispered, her masklike face twisted in a smile. “You know that I met her once, at a seminar in Washington. Reid Malenfant himself introduced us. She was fascinated by Venus. She would have loved to go there, to a new world.”

Guilt, the great motivator.

But Nemoto was right. Her mother had grown to love Venus, this complex, flawed sister world of Earth. She used to tell her daughter fantastic bedtime tales of how it would be to sink tothe base of those towering acid clouds, to stand on Venus itself, immersed in an ocean of air.

But her mother’s studies had been based on scratchy data returned by a handful of automated probes, sent by human governments in the lost pre-Gaijin days of the last century. When the Gaijin had showed up, all of that had stopped, of course.