The live of one single star is but a heartbeat in the vastness of the universe. And the birth pangs of one particular star draws our attention to the galaxy named milky way, to a sector called Sagittarius' Arm, actually the outskirts of our milky way, galactic backwoods, if you like. Very fast, very hot. But not like the central star, those whirls contract, taking on a spherical shape, cooling down more and more. Haphazard makes the smaller whirls become planets, while the larger one is destined to become a sun.
Solid matter is accumulated, which enhances gravitation, which, again, intensifies contraction.
The asteroid belt between Mars and Jupiter is hypothesized to be its debris. Our fictional journey brings us something like ten light-years away to a part of a star constellation that is seen from Earth as the constellation Eridanus . Here, we register a central whirl of interstellar gas and five minor ones, corresponding with five planets that are taking shape. Our focus is set on the fourth and the fifth, smaller planet. They form what is usually filed under double-planet, being very close to one another.