"Kim," said Dona presently. "It's stupid of me, but I don't see how you're going to learn the secret."
Kim put the picture on the enlarger, for examination in a greater size.
"They made the shield to keep things out," he said wearily. "Radiation, charged particles, neutrons—everything. The planet simply can't be reached, not even by matter-transmitters, when the shield is up. But by the same token nothing can leave the planet either. It can't even be spotted from space, because the light of the sun isn't reflected. It's deflected to a right-angled course. You might pick it up if it formed a right-angled triangle with you and the sun, or you might spot it in transit across the sun's disk. But that's all."
"Yes."
"The shield was a special job," said Kim. "For a special purpose. It was not a weapon. But there were all those planets that could be grabbed if only Ades were knocked out. So why shouldn't King Pharos sneak a force-field generator on to Ades? When the field went on, Ades would be invisible and unreachable from outside. And the outside would be unreachable from it. Space-ships couldn't get through the field. Matter-transmitters couldn't operate through it. If a few technicians were sneaked to Ades as supposed exiles and promised adequate reward, don't you think they'd hide out somewhere and turn on that field, and leave it on until the folk on Ades had starved or gone mad?"
HORRIFIED, Dona stared at him. She went pale. "Oh—horrible! The sky would be black—always! Never a glimmer of light. No stars. No moons. No sun. The plants would die and rot, and the people would grow bleached and pale, and finally they'd starve."
"All but the little gang hidden away in a well-provisioned hideout," said Kim grimly. "I think that's what's happened to Ades, or is happening. And this is the solar system where the little trick was worked out. I'd hoped simply to raid the generator and find out how it worked, which would be dangerous enough. Look!"
He pointed to the projected image of the sun. There was a tiny dot against its surface. It was almost, it seemed, bathed in the tentacular arms of flaming gases flung up from the sun's surface.
"There's the planet," said Kim. "At its closest to the sun! With the shield up, so that nothing can reach its surface. Nothing! And that includes space-ships such as this. And at that distance, Dona, the hard radiation from the sun would go right through the Starshine and kill us in seconds before we could get within millions of miles of the planet. If there's any place in the universe that's unapproachable, there it is. It may be anything up to three months before the shield goes down even for fractions of a second at a time. And my guess is that the people on Ades won't last that long. They've had days in which to grow hopeless already. Want to gamble?"
Dona looked at him. He regarded her steadily.
"Whatever you say, Kim."
"Sixteen million lives on Ades, besides other aspects of the situation," said Kim. "The odds against us are probably about the same, sixteen million to one. That makes it a fair bet. We'll try."
He got up and began to tinker with the radiation-operated relay which turned off the transmitter-drive. Presently he looked up.
"I'm glad I married you, Dona," he said gruffly.
As the Starshine moved closer in, the feeling in the control-room grew tense. The little ship had advanced to within twenty millions of miles of the blue-white sun, and even at that distance there was a detectable X-ray intensity.
Kim had turned on a Geiger counter, and it was silent simply because there was no measurable interval between its discharges. A neutron detector showed an indication very close to the danger mark. But Kim had the Starshine's nose pointed to the intolerably glaring sun.
The electron telescope showed the sun's surface filling all its field, and because the illumination had been turned so low, raging sun-storms could be seen on the star's disk. Against it, the black silhouette of the planet was clear. It was small. Kim estimated its diameter at no more than six thousand miles. The Starshine's gyros hummed softly and the field of the telescope swayed until the planet was centered exactly.
There was a little sweat on Kim's forehead.
"I—don't mind taking the chance myself, Dona," he said, dry-throated. "But I hate to think of you. . . If we miss, we'll flash into the sun."
"And never know it," said Dona, smiling. "It'll be all over in the skillionth of a second—if we miss. But we won't."
"We're aiming for the disk of the planet," t he reminded her. "We have to go in on transmitter-speed to cut the time of our exposure to hard radiation. That speed will make the time of exposure effectively zero. But we have to move at a huge multiple of the speed of light, and we have to stop short of that planet. It may not be possible!"
"Do you want me to press the button, Kim?" Dona said softly.
He took a deep breath. "I'll do it. Thanks, Dona."
He put his finger on the stud that would throw the ship into transmitter-drive, aimed straight at the disk of planet against the inferno of sun beyond. There was nothing more certain than that to miss the planet would fling them instantly into the sun. And there was nothing more absurd than to expect to come out of transmitter-drive within any given number of millions of miles, much less within a few thousands. But—
Kim pressed the stud.
Instantly there was blackness before them. A monstrous, absolute blackness filled half the firmament. It was the force-field-shielded planet, blotting out its sun and half the stars of the galaxy. Kim had made a bull's-eye on a target relatively the size of a dinnerplate at eleven hundred yards. More than that, he had stopped short of his target, equivalent to stopping a bullet three inches short of that plate.
He said in a queer voice:
"The—relay worked—even backward, Dona."
CHAPTER VIII
Dark Barrier
FOR a time Kim sat still and sweat poured out on his skin. Because their chances had seemed slight indeed. To stop a spaceship at transmitter-speed was impossible with manual means, anyhow. It could cross a galaxy in the tenth of a millisecond. So Kim had devised a radiation-operated relay which threw off the drive when the total radiation reaching a sensitive plate in the bow had reached an adjustable total.
If in an ordinary flight the Starshine headed into a sun—unlikely as such an occurrence was—the increased light striking the relay-plate would throw off the drive before harm came. But this time they had needed to approach fatally close to a star. So Kim had reversed the operation of the relay. It would throw off the drive when the amount of light reaching it dropped below a certain minimum. That could happen only if the ship came up behind the planet, so the sun was blacked out by the world's shadowed nightside.
It had happened. The glare was cut off. The transmitter-drive followed. The Starshine floated within a bare few million miles —perhaps less than one million—of a blue-white dwarf star, and the two humans in the ship were alive because they had between them and the sun's atomic furnaces, a planet some six thousand miles in diameter.