"Thundering Worlds" (1934) by Edmond Hamilton, up on Fantastic Worlds
This story is justly famous as an example of the sheer scope possible in science fiction within even a short story in science fiction. Here, faced with the death of the Sun, the humanity of a future Solar System comes up with a grand solution to the problem of interstellar migration -- and faces perils on an equally-grand scale. This tale was one of the reasons why Hamilton acquired the cognomen of "World-Wrecker" ...
"Thundering Worlds"
© 1934
by
Edmond Hamilton
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Standing with Hurg of Venus at the window, I pointed up at a number of dark, long shapes sinking out of the gray sky. "There come our fellow Council-members," I said.
Hurg nodded. "Yes, Lonnat-that first ship looks like that of Tolarg of Pluto, and the next two are those of Murdat of Uranus and Zintnor of Mars."
"And the last one is that of Runnal of Earth," I added. "Well, the solar system's peoples will soon know how we of the Council decide on the plan, whether it's accepted or rejected."
"Most of them are praying it will be accepted," Hurg said. "If it were not for Wald of Jupiter and your enemy, Tolarg of Pluto, I would be sure it would be accepted, but as it is-"
He lapsed into thoughtful silence and I too was silent with my thoughts as we gazed out of the window. The panorama that stretched before us was enough to make any man think.
We were gazing across the city of dome-shaped metal buildings that completely covered the planet Mercury. Many flyers, torpedo-shaped craft propelled by atomic blasts, swarmed over the city, rising from or descending into the heat-locks at the tops of the buildings. In the snow-sheathed streets between the buildings no people at all were to be seen. Long ago Mercury had grown too cold for life in the open.
Mercury cold? Mercury, the innermost of the sun's nine planets, that had once been heated almost to furnace-temperatures by the blazing sun? That had been many ages before, though, when the sun was hot and yellow and in the full tide of its middle-life. It was not such a sun that hung in the gray heavens over Mercury now. No, the sun above us was a huge sullen blood-red disk, a darkening crimson sun which gave forth little heat and light. It was a sun that was dying! Yes, our sun was dying! It no longer cast out a flood of heat and light on its nine planets, and the others were even icier and colder than this one of Mercury. Long ago in the past. men had journeyed out from the planet of their origin, the world Earth, to the sun's other worlds (1).
They had colonized all the nine planets from Mercury to Pluto, until each held a great human population. Their inter-planetary ships filled the ways between the worlds, and the whole system was ruled by a Council of Nine in which each member represented the planet of which he was the head.
This stable civilization of man in the solar system had lasted for ages upon ages. It had seemed that nothing could ever threaten it. But it was threatened at last and by a most awful menace. The sun was cooling! It was changing from yellow to red, following the course that every sun follows, and as it cooled, its planets became colder and colder. Their peoples were forced to live in cities of artificially heated dome-buildings, and move about in enclosed, warmed flyers. And still the sun cooled until men saw that in the near future it would become completely dead and dark, and that life upon its worlds would then be impossible in the awful cold.
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How will this future humanity survive the death of the Sun? Find out the answer when you read their epic odyssey in Fantastic Worlds!