He took the stylus and began calculating. He talked as he worked, telling the Planeteers exactly what they were up against. "I'm figuring out where to put the charge so it will do the most good, but my data isn't complete. If our homemade bomb goes off, I don't know exactly how much power it will give. If it gives too much, we'll be driven so close to the sun we'll never get free of its gravity." Bradshaw, the English Planeteer, said mildly, "Don't worry, Lieutenant. If it isn't the solar frying pan, it's Connie fire." A chorus of agreement came from the other Planeteers. "What a crew!" Rip thought. "What a great gang of space pirates!" He finished his calculations and found the exact place where Kemp would cut. A few feet away from the spot was a thick pyramid of thorium. That would do, and they could cut into it horizontally instead of drilling straight down. He pointed to it. "Let's have a hole straight in for six feet. And keep it straight, Kemp. Allow enough room for a lining of nuclite. Koa, cut a sheet of nuclite to size." Kemp's torch already was slicing into the metal. Rip asked, "Can you weld with that thing, Kemp?" "Just show me what you want, sir." "Good." Rip motioned to Trudeau. "Frenchy, we'll need a strong rod at least eight feet long." The French Planeteer hurried off. Rip consulted his chronometer. Less than ten minutes had passed since the call from Terra base. He went over his plan again. It had to work! If it didn't, asteroid and Planeteers would end up as subatomic particles in the sun's photosphere, because he had calculated his blast to drive the asteroid past the limit of safety. It was the only way he could be sure of putting them beyond danger from Connie landing boats or snapper-boats. The Connie would have only one chance--to bring his cruiser down. If he tried that, Rip thought grimly, he would get a surprise. The second nuclear charge would be set, ready to be fired. The Connie cruiser was so big that no matter how it pulled up to the asteroid, some part of it would be close enough to the charge to be blown into space dust. No cruiser could survive an atomic explosion within five hundred yards, and the Connie would have to get closer to the nuclear charge than that. Dominico reported that the bomb had been dismantled. Rip went to it and examined the raw plutonium, being careful to keep the pieces widely separated. This particular bomb design used five pieces of plutonium which were driven together to form a ball. Rip made a quick estimate. Two were enough to form a critical mass. He would use two to blast into the sun and three to blast out again. He would need the extra kick. There was only one trouble. The pieces were wedge shaped. They would have to be mounted in thorium in order to keep them rigid. Only Kemp could do that. They had no cutting tool but the torch. Santos appeared, carrying a rocket head under each arm. They had wires wound around them, ready to be attached to an electrical source.