later it will happen to cross the orbit of its goal at the same time that the goal is there. In other words, if we head for Mars, we ignore where Mars is when we take off, but head for the spot in space where it will be when we reach that spot.”
“You mean,” Bruce put in, “something like making a date to meet a friend at a place where you and he both must travel to get to.”
“That’s the idea,” said his father. “And since we can’t ask the planet to go some special way, we have to do all the planning to be where the planet will be going.”
“Well, then,” said Bruce, “aren’t we simply going to find out where Saturn will be and go there directly?” “No,” was the engineer’s answer, “because that would require traveling all that far way against the pull of the sun. Such an orbit would require immense amounts of energy to establish, because instead of merely breaking away from the pull of the Earth, which is hard enough as you know, we would have to fight all the way against the pull of the sun itself. Saturn is farther away from the sun than the Earth, eight hundred million miles farther, since our home planet is only ninety-two million miles ‘upward’ from the sun. This is a pull which would require blasting all the way and no ship could carry that amount of fuel. “So what we are going to do is to hitchhike our way!” “Whaaat!” said Arpad incredulously. “How can you do that?”
Garcia, who had stopped his work at last, smiled, looked up. “We’ll thumb a ride on the asteroids.” Rhodes nodded. “Exactly. It so happens that the tiny little planets called asteroids that mostly revolve between Mars and Jupiter give us our steppingstones. There are thousands of these little worlds and some of them, fortunately for us, have very wild orbits.”
“Yes, that’s right,” said Bruce excitedly, “some of them come close to the Earth, too. There’s Eros and Amor and Adonis—they all come to a few million miles of the Earth.”
Rhodes nodded. “There are asteroids that go clear inward to the orbit of Venus, nearer the sun than ourselves. And what interests us more, there are some that go out way beyond even Jupiter. One especially, named Hidalgo, goes almost out to the orbit of Saturn itself.”
“Then are we going to Hidalgo?”
“Not directly, that’s impossible,” said Rhodes, “but that will be our final hitching post. Hidalgo happens right now to be passing the orbit of Jupiter and to be heading almost directly for Saturn. If we can catch it in time, we can simply ride it almost all the rest of the way.
“But were not even going to go there directly. We’re going to pick up a near asteroid first, one near the Earth that’s heading outward. We’ll ride it beyond the orbit of Mars, where we’ll jump off it and jump onto another asteroid that will take us most of the way through the asteroid belt. Then we'll leave that one for another that will take us near Hidalgo, where we can make our landing. We’ll settle down on Hidalgo for a few weeks until we are close to Saturn, and then we’ll make our final leap to our real objective.”
“Wow!” said Arpad, while Bruce whistled.
“It took plenty of figuring,” said Garcia, shaking his head over his machines. “Plenty. We had to work out the orbits of dozens and dozens of these little worldlets. We had to figure speeds and directions and timing. That’s why we’re wasting fuel now trying to get back to where we should have been if we had followed our original calculations. Otherwise the new figures will be terribly difficult.”
“Then, actually we won’t do too much flying, only short hops between asteroids, letting their own orbital force carry us along against the sun’s pull,” contributed Bruce again, studying the chart with its circles tangled in each other like the web of a drunken spider.
“Correct,” said Rhodes.
At that moment Jennings called
“You mean,” Bruce put in, “something like making a date to meet a friend at a place where you and he both must travel to get to.”
“That’s the idea,” said his father. “And since we can’t ask the planet to go some special way, we have to do all the planning to be where the planet will be going.”
“Well, then,” said Bruce, “aren’t we simply going to find out where Saturn will be and go there directly?” “No,” was the engineer’s answer, “because that would require traveling all that far way against the pull of the sun. Such an orbit would require immense amounts of energy to establish, because instead of merely breaking away from the pull of the Earth, which is hard enough as you know, we would have to fight all the way against the pull of the sun itself. Saturn is farther away from the sun than the Earth, eight hundred million miles farther, since our home planet is only ninety-two million miles ‘upward’ from the sun. This is a pull which would require blasting all the way and no ship could carry that amount of fuel. “So what we are going to do is to hitchhike our way!” “Whaaat!” said Arpad incredulously. “How can you do that?”
Garcia, who had stopped his work at last, smiled, looked up. “We’ll thumb a ride on the asteroids.” Rhodes nodded. “Exactly. It so happens that the tiny little planets called asteroids that mostly revolve between Mars and Jupiter give us our steppingstones. There are thousands of these little worlds and some of them, fortunately for us, have very wild orbits.”
“Yes, that’s right,” said Bruce excitedly, “some of them come close to the Earth, too. There’s Eros and Amor and Adonis—they all come to a few million miles of the Earth.”
Rhodes nodded. “There are asteroids that go clear inward to the orbit of Venus, nearer the sun than ourselves. And what interests us more, there are some that go out way beyond even Jupiter. One especially, named Hidalgo, goes almost out to the orbit of Saturn itself.”
“Then are we going to Hidalgo?”
“Not directly, that’s impossible,” said Rhodes, “but that will be our final hitching post. Hidalgo happens right now to be passing the orbit of Jupiter and to be heading almost directly for Saturn. If we can catch it in time, we can simply ride it almost all the rest of the way.
“But were not even going to go there directly. We’re going to pick up a near asteroid first, one near the Earth that’s heading outward. We’ll ride it beyond the orbit of Mars, where we’ll jump off it and jump onto another asteroid that will take us most of the way through the asteroid belt. Then we'll leave that one for another that will take us near Hidalgo, where we can make our landing. We’ll settle down on Hidalgo for a few weeks until we are close to Saturn, and then we’ll make our final leap to our real objective.”
“Wow!” said Arpad, while Bruce whistled.
“It took plenty of figuring,” said Garcia, shaking his head over his machines. “Plenty. We had to work out the orbits of dozens and dozens of these little worldlets. We had to figure speeds and directions and timing. That’s why we’re wasting fuel now trying to get back to where we should have been if we had followed our original calculations. Otherwise the new figures will be terribly difficult.”
“Then, actually we won’t do too much flying, only short hops between asteroids, letting their own orbital force carry us along against the sun’s pull,” contributed Bruce again, studying the chart with its circles tangled in each other like the web of a drunken spider.
“Correct,” said Rhodes.
At that moment Jennings called
Similar Books
