The distribution of impact craters would be significant, she thought quickly. Corroborative, in fact. On Mars and the Moon there was a clustering of craters, in certain regions. On Mars, you had one young hemisphere, smooth and unblemished, the other heavily cratered, ancient. The same on the Moon, with its separation into the younger seas and the ancient highlands.

Here — if I’m right — it would be different. The craters must be uniformly distributed, right across the planet’s surface.

All we’d need is a reasonably detailed global map of the surface, and to do a simple crater count. Then we’d know.

But that map wasn’t available, and it wasn’t going to be. Not in her lifetime.

The radar mapping from this flyby would be the most detailed ever performed, but would be confined to a strip wrapped around one side of the planet. Any crater counts based on that were going to be tentative, at best.

She slammed her fist into a working surface. Stone glanced at her, surprised; she kept her eyes averted from his face.

Damn. We shouldn’t be here! A fifty-million-buck radar mapper in polar orbit would settle this. And they spent more than that on the backup john for this tin can of ours.

For fifteen years, most of NASA’s budget had been sucked into manned spaceflight. Unmanned projects had been subordinated to the needs of the Mars mission or cut altogether. They had lost a gravity-assist flight to Venus and Mercury, asteroid and comet encounters, Grand Tour probes to the outer planets. The Large Space Telescope, a big Earth-orbital eye, had also been axed.

Sure, humans were on the way to Mars. But humanity knew nothing of the rest of the Solar System it hadn’t known in 1957: the moons of Jupiter and Saturn remained points of light in the sky, the disks and rings of the giant worlds a telescopic blur.

And I’m cooperating with it, she thought sourly. After all my great moral pronouncements, I’ve finished up as guilty as the rest. Maybe, because I know better, more so.

The screen filled up with static.

The probe had imploded, crushed by the pressure.

York checked the time. It was just fifty-five seconds after landing.

Gershon pushed himself away from his console. “Well, there you have it. Venus is, officially, a shit-hole.”

And then, suddenly, the cabin grew perceptibly darker. She glanced up. As Ares sailed into the shadow of Venus, the last crescent sliver thinned out into a hoop of light — it was suddenly multicolored (I hope the cameras are getting this) — and then it faded and died away.

There was a hole in space, above Ares: it was the blackness of the cloud decks of Venus, empty, scorching, lifeless.

York returned to her station. “The TV mosaics have started,” she reported. “And the planetary strip photography. Everything’s nominal on the pallet.”