The Currents of Space
Isaac Asimov
 The story takes place in the backdrop of Trantor's rise from a large regional power to a galaxy-wide empire, unifying millions of worlds. This story occurs around the year 11,000 AD (originally 34,500 AD, according to Asimov's early 1950s chronology), when the Trantorian Empire encompasses roughly half of the galaxy. The independent planet Sark exploits the planet Florina and derives its great wealth from "kyrt", a versatile and fluorescent fiber that can only be grown on Florina. The relationship between the two planets is analogous to the situation between European imperial powers and their colonies during the 19th century, where the Florinians are forced to work in kyrt fields and are treated as an inferior race by the Sarkites. Attempts to break the Sark monopoly and grow kyrt on other worlds have thus far been unsuccessful. Meanwhile, Trantor would like to add these two worlds to its growing empire. There is a hidden irony in Sark's dominion over Florina: clear parallels to the American South growing cotton with slave labor. The Florinians are one of the lightest-skinned people in a galaxy where racial categories seem to have been forgotten, except by the people of Sark. One of the characters, Dr. Selim Junz, comes from Libair, a planet with some of the galaxy's darkest-skinned people, and feels sympathy for the Florinians. (The planet Libair takes its name from Liberia, a country in Africa, which would explain a dark-skinned genetic inheritance. Liberia was also settled by freed slaves from America.) Also, Asimov chose the name of "kyrt" to be rather similar to "cotton", and he explains that it contains cellulose. The possible destruction of Florina is predicted by Rik, a "spatio-analyst", who has had his mind manipulated by a "psychic probe" device, resulting in gross amnesia. When Rik gradually starts remembering his past, it produces a political crisis involving Sark, Florina, and Trantor. Rik, a native of the Earth, had discovered that Florina's sun is about to explode into a nova because it is being fed carbon by one of the outer-space "currents of space", supposedly rather like the currents of the ocean. It is also revealed at long last that the special energetic wavelength of light that is being emitted by Florina's sun is what causes the very high-quality kyrt fiber to grow there. This is the explanation why kyrt cannot be grown on other planets – since stars going nova are really quite rare, and stars with habitable planets that go nova are rarer still. Because losing Florina would mean losing the only source of its vast wealth, there is strong resistance from Sark to accept the message. However, when it is explained that the wealth is already lost since the conditions that enable kyrt to grow can be easily duplicated anywhere now that they are understood, they become more amenable. When Trantor offers to buy out the entire planet for a very high price, the offer is readily accepted. Even though there is not yet a full Galactic Empire, Trantor does control the now largely radioactive Earth. The idea of evacuating Earth is mentioned, but that is strongly rejected by Rik. He insists that it is the original planet of the human race, though this is not generally accepted.