He laughed, showing a two-tooth vacancy in the front of his mouth. “Funny thing is that I might’ve been a scientist if I hadn’t been given the name of one!” With that, Isaac Newton turned back to check on how the ship was running. The captain went over to converse with him, and this gave the boys an opportunity to look around the navigation room. Of particular interest was a huge chart on the back wall near the entrance. On the map were countless globes of various sizes, and running through the globes were long curving lines. “What’s that, do you suppose?” Patch asked his friend. Garry looked closely at the printed names beside the round symbols. “Hermes—Vanguard II—Adonis—Derelict Space Ship _Oberon_,” he read. “These seem to be objects floating about in space,” he said, “and the lines through them must be their orbits.” “You’re very observant, Garry.” Garry looked back and saw that Captain Eaton had come over. “That’s exactly what they are, and we have to know exactly where each one of them is at all times,” the captain said. “If we missed keeping up with one, we might run into a collision orbit with it, and then it would be quickly over for all of us. Some of the objects are asteroids, some man-made satellites, some large meteor fragments whose orbits we have already plotted. And a few are derelicts, or empty shells of what were once proud space liners. Any one of them could destroy the _Carefree_ if it should hit us. In fact, a meteor as large as an orange could wreck us because of the terrific velocity at which it would strike.” “Gee,” Patch said, “you must be anxious all the time about being hit by something.” “No. It’s a risk, of course, but space is so very, very huge that actually there is little chance of being hit by anything any larger than a grain of sand. But of course there is always the chance that someday the big, unexpected one will come. Still, we don’t worry about it because it would keep us from enjoying our life in space.” Captain Eaton showed the boys some of the other things in the room. He explained the purpose of the various dials and switches on the console—facts that the boys would have given anything to know when they were so desperately trying to steer the space taxi. The skipper of the _Carefree_ told them that usually there was only one pilot on duty but that, in case of tricky navigation or on other special occasions, both Mac and Isaac or Ben would be on together. The captain added that he was quite a pilot himself and liked to take over the controls now and then. Suddenly chimes were heard over a loud-speaker. “That’s the signal for us to get ready for lunch,” Captain Eaton said. “Let’s go, fellows, and wash up.” “Tell Mac to shake a leg and get up here to relieve me, will you, Captain?” Isaac asked. “I’m starved. It’s been a long shift.” “I will, Isaac,” the captain promised, and pushed the button which opened the door.