CHAPTER 22
After her last zero-zero leap, Envoy paused a while, some seven astronomical units from her goal. Again Dayan and Cleland took instruments out onto the hull.
The destination sun glared as bright as Sol at the orbit of Saturn; it was a KO, with about two-thirds the luminosity. Already the searchers knew that eight worlds attended it, that the second was in the zone of habit-ability and indeed had an oxynitrogen atmosphere, and that thermonuclear power plants operated not only on it but at several other sites around the system. Now they gathered more data, more precise, for forecasts and warnings.
For a long span, however, their attention was on a point where eyes found nothing but the dark. Meter readings computed numbers, graphic displays bore them the tidings. Their hearts knocked.
“Yes,” Dayan said, “there’s no more doubt. A pulsar, within one-third parsec of us. And it has planets.”
No mere white dwarf like Sirius B — a neutron star, self-compressed remnant of a giant that burst itself asunder, clinker still shooting its furious radio beams into space with no message but its own ferocity — Unless ships from Earth had traveled well beyond Sol’s neighborhood since Envoy left, humans had never before been this close to one.
“Wouldn’t the supernova have sterilized the planet here?” Cleland saw immediately that his question was stupid, blurted in excitement.
Dayan’s head shook, shadowy behind the helmet. “No, it wasn’t near at the time. High proper motion; it’s only passing by. I’ve detected an expanding nebulosity yonder.” She pointed at another object which distance made invisible. “If it’s from the eruption, then that happened about a thousand light-years off and ten million years ago.”
“Only ten million? M-my God, those planets must still be re-evolving!” Dayan’s own voice quivered. “Yes, and the pulsar itself probably hasn’t reached a steady state yet. The physics —” She set about directing instruments to more urgent concerns. “I imagine the Yonderfolk can tell us about it,” she finished a bit harshly.
Envoy proceeded inward at a full g, ignoring economy, to cut the passage time down to a week. Her people were impatient.
“Look at that,” Kilbirnie breathed. “Just look at that.”
“Apa Isten.” Ruszek did not seem to notice he had crossed himself.
The ship was passing within twelve million kilometers of the third planet. Her crew had gathered in the reserve saloon-galley to see what her optics could screen for them. Magnified and enhanced, a thick crescent stood ruddy, mottled — and silver-spotted with seas. Air slightly blurred the limb and softened the edge between day and night. Clouds, elongated and patchy rather than marbling, shone less brilliantly white than Earth’s; but they shone. Three firefly sparks glinted against the blackness beyond, satellites. Instruments had found at least a dozen more.
Only a third again as big as Mars, receiving at its distance no more light from the weaker sun, the globe should have been a similar desolation, its atmosphere almost as thin. But: barely discernible as a shimmer where sunlight struck at particular angles, a transparent shell enclosed it, twenty-odd kilometers greater in radius. A few of the travelers thought they could make out one or two of the pillars upholding the structure. Spectroscopy showed the air within to be thicker than Earth’s, and as warm. It was carbon dioxide, nitrogen, water vapor, traces of methane and other gases, nothing to sustain creatures with lungs. Nevertheless waters and land gave reflection spectra of complex organic materials. Life-stuff?
“Those satellites are neutrino radiators,” Dayan said. Not everyone aboard had yet heard of her newest discoveries. “Thermonuclear reactors. I think they’re beaming energy down to the planet, heating it. And there are areas of violent activity on the surface. The waste heat from them contributes.” Awe underlay her dry words.
“The Yonderfolk are terraforming,” Mokoena marveled.
Sundaram smiled, less calmly than he was wont. “Not precisely ‘terra,’ Mam.”
Cleland spoke confidently, in his element. “It can’t be that simple. I daresay they brought in ices from comets, and roofed everything in to keep volatiles from escaping. Probably the shell also filters out excessive ultraviolet and screens off hard radiation. The planet’s not massive enough to have much of a magnetic field for protection, if any. But neither can it have plate tectonics. How do they propose to maintain the carbonate-silicate cycle and the other equilibria necessary for life to last? For that matter, transforming raw gases into breathable air and rock into soil takes huge amounts of energy. Which means time — geological time.”