The long hours passed, and only Rip's chronometer told him when the end of a day was reached. The Planeteers alternately worked on the surface and rested in the air of the landing boat compartment, while the asteroid sped steadily on its way.
When a series of sightings over several days gave Rip enough exact data to work on, he recalculated the orbit, found the amount that the course had to be corrected, and supervised the cutting of new holes in the metal.
Tubes of ordinary rocket fuel were placed in these and fired, and the thrust moved the asteroid slightly, just enough to make the corrections Rip needed. It was not necessary to take to the landing boat for these blasts. The Planeteers retired to their cave, which was now lined with nuclite as a protection against radiation.
Rip watched his dosimeter climb steadily as the radiation dosage mounted. Then he took the landing boat to the Scorpius, talked the problem over with the ship's medical department, and arranged for his men to take injections that would keep them from getting radiation sickness.
They left the asteroid belt far behind and passed within ten thousand miles of Mars. The Scorpius sent its entire complement of snapper-boats to the asteroid for protection, in case Consops made another try, then flamed off to Marsport to put in new supplies to replace those damaged when Rip had forced sudden and disastrous acceleration.
The asteroid had reached Earth's solar orbit before the cruiser returned, though Earth itself was on the other side of the sun. Rip ordered a survey and found the best place on the dark side to make a new base. The Planeteers cut out a cave with the torch, lined it with nuclite, and moved in the supplies. It would be their base to the end of the trip.
The sun was very hot now. On the sunny side of the asteroid the temperature had soared far past the boiling point of water. But on the dark side, Rip measured temperatures close to absolute zero.
When the Scorpius returned, he arranged with Commander O'Brine for the Planeteers to take turns going to the cruiser for showers and decent meals.
The asteroid approached the orbit of Venus, but the bright planet was some distance away, at its greatest elongation to the east of the sun. Mercury, however, loomed larger and larger. They would pass close to the hot planet.
O'Brine recalled Rip to the Scorpius and handed him a message.