"I hope they didn't use a pictorial alphabet like Chinese," said Joe, looking over Mark's shoulder.

"No," the big Starman answered. "There are plenty of recurring symbols, so I a.s.sume it's a language like our own, with letters and words.

Somebody will be able to decipher this without too much difficulty.

It's far beyond my skill, though." He rubbed his chin. "But I can recognize a lot of the machinery."

Zip was sitting nearby. He hadn't spoken much during breakfast. The images of the farm pulled at him again. "Mark, Joe," he began. He hesitated a moment while they turned to him. They could see he was puzzling through something, and waited patiently for him to continue.

"SE says that Zimbardo has targeted Earth with an asteroid over forty miles long. What'll that do to home?"

Mark was suddenly deeply saddened. Zip always referred to the Moon as home. He spoke softly.

"One of my professors at Starlight University talked about a study conducted in the early 21st century. Back then, scientists started becoming concerned about asteroid impacts, and they built a complex computer model to see what would happen if a large asteroid struck Earth."

"What did they find?" whispered Joe.

"Well, the model found that, depending on the angle of entry, the impact can produce a ma.s.sive corridor of incineration ahead of the impact site. In that area, just about all life ends in minutes. But the model predicted other changes that destroyed nearly all life on Earth within a few years."

"Like what?" Zip's voice was dusky.

"I'm sounding like a textbook," complained Mark.

"Go on," insisted Zip.

Mark closed his eyes and tilted his head back. "A few hours after the impact, clouds of noxious gases billow up and block out the sun for months. Temperatures drop drastically all over the Earth and corrosive acid snow and rain fall. These short-term effects alone-intense cold, darkness, and acid rain and snow-kill the plants and photosynthetic plankton, the base of most food chains. Herbivores starve, and then the carnivores that feed on the herbivores starve. This is enough to kill most of the remaining human life on the planet. After the clouds clear, the atmosphere is thick with carbon dioxide from fires and decaying matter. Then the carbon dioxide contributes to global warming that lasts for ages."

Tears slowly escaped from Zip's closed eyes and made tracks down his cheeks. He remembered that when he was small his aunt and uncle had taken him on a two-hour flight in their small plane to the place closest to their home where there was a field of nuclear devastation.

His first view of the terrain beyond the boundary had been indelibly burned into his seven-year-old mind. The cities and towns surrounded by fields, orchards, streams, ponds, and woods had rapidly tapered off below a slight rise into a land of gray, utterly lifeless, gasping dust thatreached as far southeastward as the eye could see. The center of the field had been the nation's capital, the third of the great American cities to be destroyed in the holocaust of 2048.

"How big was the asteroid they modeled?" asked Joe.

"About six to ten miles across," said Mark.

"And the one Zimbardo has aimed at Earth is forty miles long?"

"Bigger. A little bigger than that," answered Zip quietly. "Bigger." He felt a chilling darkness come over him, almost as if he had walked into an inky refrigerator. He shivered uncontrollably for a moment, then sat up and took control of himself.

"Today we get the Star Ranger back!" he announced in a clear voice.

"and we're heading back to Earth! Be ready for immediate departure!"

An immense metal and gla.s.s wheel, half a mile in diameter, rotated slowly in the jeweled heavens. It was the primary manufacturing and launching headquarters of Nolan Mining Enterprise. It orbited the Moon about 500 miles above the surface.

Robert Nolan was burning with a zealous flame of energy. Although often close to burning out, he never went over the edge. His apparently bottomless resources had allowed him to achieve remarkable things in twenty years. Now he was in the command bubble that lifted like an antenna from the heart of the s.p.a.ce station. A tower two hundred yards long lifted out from the plane of NME's manufacturing and launching facility. At its end was a large observation and control center that commanded a view of every aspect of one side of the plant.

"Launch in forty-three minutes exactly," said an operative in the command bubble. Nolan stood, looking intently over the man's shoulder at the screen in front of him. Nolan's eyes shifted repeatedly back and forth from the screen to the actuality that lay spectacularly open to view before him.

"Sir?" said another technician, turning toward Nolan. "The Lux Mundi has now completed docking." The Lux Mundi was Richard Starlight's personal s.p.a.cecraft.

"Excellent, John," said Robert Nolan. "Please have Mr. Starlight sent up here without delay."

"Yes sir." The technician turned back to his station and issued commands. In less than four minutes, an elevator brought Richard Starlight into the center of the command bubble of Nolan Mining Enterprise. He stepped out onto the floor and looked around quickly.

"Over here, Rick," said Nolan, stepping toward his friend.

"Bob! Good to see you!" The men shook hands briefly. "All went well at our end," Richard whispered.

Nolan stepped back and spread his hands toward the launching arena of the s.p.a.ce station.

"Terrific news," he said. "We'll be launching in about forty minutes."

The two men went into Nolan's office and sealed it. Though everything was visible through clear part.i.tions, no one could hear what went on inside.

"I'm so sorry I fell apart at that meeting, Rick," Robert began.

"Don't give it a thought, Bob. You've done very well for the project since then. This is a great offering you're making."

"The least we can do, in addition to making as many of the microwave probes as we could, is provide these freighters."

"Ahead of schedule, too, by a little bit. All the companies pulled together and made the probes to Dr. Hoshino's specifications. I like his design. His plan should work very well, very well indeed!"

"It's a wonderful design, Rick! Dr. Hoshino is a genius to a degree above everyone else of this generation. We ought to be able to locate any asteroid that Lurton Zimbardo throws at us. But stopping it is a different problem."

"If we find it in time, that shouldn't be too hard, either."

The two friends talked for a little longer, then went out to watch the launch. Seven unmanned NME freighters were prepared to carry Earth's hope into s.p.a.ce. They would be accompanied by a dozen armed ships supplied by s.p.a.ce Command. The rendezvous of freighters and warships was only a half-hour's flight time from the s.p.a.ce station. Then they would proceed on the eight-day journey to the site of deployment.

In a private office and laboratory below, Robert Nolan's chief a.s.sistant Beowulf Denn finished making a voice recording of the details of the launch. He included the number of freighters, the number and type of s.p.a.ce Command warships appointed to guard them, their course, hour of departure, and timing of the deployment of the probes.

When he had finished the recording, he inserted the disk into a computer independent of the NME computer system and speeded up its contents so that the entire message was less than 0.03 seconds long. He then encrypted it and transmitted the result on a tight beam communicator to coordinates in s.p.a.ce which he kept only in his head.

After the message had been sent, he destroyed the disk and removed all signs on his computer that the action had occurred. The message he sent could be read only one time and then would erase itself, leaving no trace at the receiving end that it had ever existed.

Seven ships had arrived at O344. The Starmen were outside, having sped through the airlock with the first news that the ships from Ceres were at hand. They stood on the edge of the landing zone and watched the ships come close to O344. Only the dark red Star Ranger and one other ship touched down. Sim Sala Bim was the first to debark.

"So pleased to see you young men are safe!" he spouted. "So much has happened in these three weeks! Here is your Star Ranger, ready for duty!" The Indian was excited. Zip had shaken off his own dark mood and was rising to the challenge. The other two Starmen were eager to lift off and get back into the battle against Lurton Zimbardo.

"Nice to see you, Sim!" cried out Zip, as he and the man from Ceres shook hands through their s.p.a.cesuits. "George and his men will be ready in a moment. They are wonderful people! Salt of the earth types, though I'll bet none of them has been on Earth for years!"

"We'll get them back to Ceres safely, don't worry about that!" advised Sim. "You just go on and stop this crazy fellow."

"Let's get going, Starmen!" urged Zip. They had already made their farewells to the asteroid miners, and had decided to leave the alien ship on O344 for research in a less anxious time. Joe had sealed it and seen that it was securely clamped to the asteroid's surface.

Within a few minutes, the Starmen were aboard the Star Ranger in their accustomed places.

Just before they lifted off, Zip turned on his communicator.

"George," he said. "Thanks for your friendship. You gave me a gift I don't think you're even aware of."