Demeter joined her regard to his and whispered, “I knew we would be awed, but this—”
“Yes, we certainly had to come look close up,” he said as low. “Already I find things I can’t explain, things we probably couldn’t have noticed from home base.”
She took her own refuge in straightforward science. “Like the reason the disc is so bright?”
He formed a chuckle. “Give us a chance to snoop around first, will you?” Thoughtfully: “Yes, they do wonder about that. No companion star to steal material from. The interstellar medium’s got to be denser hereabouts than average. My guess at the moment is that Packer’s idea is right. You remember? When the supernova went off, its gas caught up with the planetary nebula puffed out at the red giant stage, and a part has been rebounding from the shock wave ever since. It’s happened preferentially in the equatorial plane because of rotation, and gravity would reinforce this, and then as the stuff gets near there’ll be the effects of distorted space-time—maybe. We don’t know yet. Nor do we know whether this is a typical or a fluke, like maybe a quite small and close companion that got blown to bits in the explosion. We’re here to find out.”
Her voice caressed him. “Dear old bear. Metal or meat, you do like to growl on and on, don’t you?”
“Aw, you’re just saying that to make me feel good. Let’s get busy.”
Their condition had its advantages. They could commence work directly, and go for hours before they needed a download’s equivalent of sleep. If anything, the temptation in the years ahead of them would be to neglect the human side of their psyches. That could have ill consequences. They must make a point of idle talk, relived memories, participatory illusions. At the moment, though, fascination caught them up.
Initial observations went fast; the ship’s hypercomputers interpreted them faster. Guthrie and Demeter set it cruising, zigzagging inward, at accelerations that would have crushed their mortal bodies.
This was through daycycles that I cannot tell about, for we organics cannot be single-minded methodical; and as for their respites from it now and then, those belonged to them alone. I can merely say that they took pictures, spectra, meter readings from hundreds of positions and angles; they obtained long-base parallaxes; they sampled atoms, molecules, dustmotes, meteoroids, and measured the streamings of these. It was all preliminary. Probes to the black hole, and into it, were for later. But the explorers were not so distant from their origins on ancient Earth that there was not a special eagerness in this initial quest.
They found what they hoped for.
The data fell into a Euclid-clear pattern. “Planets,” Demeter said like a song. “At least two planets.”
“Well, if some pulsars have them, why not a black hole?” Guthrie replied. “The question is how.”
Can jovian or superjovian worlds in remote orbits survive a supernova blast that vaporizes lesser, closer ghosts? Most of their own mass will go likewise, the gas and ice; but might the dense cores remain, incandescent, perhaps molten, then slowly cooling? Or it is possible that an eerie rebirth takes place, whole new bodies coalescing in the less energetic fraction of the matter that burst from the giant star? However small, that fraction must still amount to several times what encircles our Sun.
“This isn’t a pulsar,” Demeter said. Her exultation shivered a little. “How violently did it die, when its remnant was too big to collapse down into quarks, but is falling in on itself forever?” Resolution returned with laughter. “Nevertheless those planets move. Let’s us!”
By now they were not far from the inner one, and laid an intercept course. Rounding its primary at a mean distance of about three astronomical units, it had a mass of about two and a half terra. The mean specific gravity, 5.8, betokened a metallic body with a rocky crust; spectral and radioactivity analysis would give details. The rotation period was 8.7 hours, with slight axial tilt. Those were the preliminary numbers. What met the travelers, as they took parking orbit and gazed out, was a terrible majesty.
Seen from there, in the ecliptic plane, the accretion disc became a double convex lens, two degrees across. Its edges hazed away in a radio blur against the stars. Inwardly the radiance heightened, until at the middle a furnace of annihilation and creation blazed gamma-white. Electrons, protons, and their antiparticles foun-tained forth, hurled on electric fields to which, even at this remove, the circuits of the ship thrummed. You, looking straight at the single octave your eyes can use, would have beheld a fierce iridescence; then you would have died. Guthrie and Demeter saw the whole fury, stopped down a thousandfold lest it burn out their sensors. They quickly turned to the planet.
At first it appeared stark as any moon. Polar caps and scattered ice fields mottled darkling mountains, uplands, plains, valleys. Impact craters were surprisingly few. Those of volcanoes exceeded them by hundreds. A smoke plume, big enough to be visible from space, declared that eruptions still went on; surely other diastrophisms did as well. Most features looked oddly smooth, as if eroded, although the highest of them must be geologically new. Subtle colors washed the underlying grays and browns, hints of rose, violet, marigold. Micalike points of brightness sparkled. Could the atmosphere be responsible? It misted the line between day and night; as the ship swept from hemisphere to hemisphere, it made vague sunrises and sunsets; but otherwise it seemed almost of vacuum clarity.
Guthrie and Demeter were a long while silent. In human phase, they would no doubt at once have sought telescopic views. As downloads, they had machine patience. They considered what was around them, absorbing it piece by piece, thinking. At the backs of their minds they sensed the instruments and computers to which they were linked, at work, as you might be half aware of some routine thing your hands are doing.
“Beautiful, in its way,” she mused at last. “And terrifying.”
“How come?” he asked.
“Oh, philosophically. So many suns and worlds in the Universe, but life so rare. This—” Her shadow self gestured. “It’s as if nature were always blindly trying to make a place for life, and nearly always failing.”
“Well she lucked out with us, and we’re carrying on the job for her. Give us a few million years.”
The argument was old between them. After all their centuries, everything between them was, save for whatever newnesses they found outside themselves. Still, they had not wearied of saying their feelings to one another, as they had not wearied of making love.
“How much time has this planet had?” she wondered.
“We should soon be able to make a pretty fair guess. The observations are taking shape. Listen.”
Presently: “Thin air, mostly nitrogen. That suggests the planets did form after the blowup, wouldn’t you say? A boiloff oughtn’t to have left any air at all.”
“And no jovian planet could have condensed this close to a working sun, especially a blue giant,” she pointed out.
“Um-m, friction with the supernova gases could’ve shortened the original orbit. But if this body dates from after the explosion, I’d have expected more of an atmosphere, considering its size. Maybe, in that environment, there weren’t a lot of comets, to bring in volatiles. Notice the scarcity of craters. We’ll want to check whether the system’s got anything like a Kuiper belt or an Oort cloud.”
He felt how she thrilled. Year upon year of discovery! However, her words stayed meditative. “Perhaps the atmosphere was originally thicker, but radiation from the accretion disc kicked most of it free. High-energy photons making ions, which the ambient electric and magnetic fields accelerated away—yes, destroying chemical compounds too, letting hydrogen break from ammonia and escape while nitrogen stayed behind—Any complex organic molecules that had formed were degraded. Maybe nothing remains on the surface but frozen carbon dioxide mingled with water ice, and… elemental carbon?”