Alustien

Alustien is a fictional planet featured in the science fiction novel "The Expanse" by James S. A. Corey. It is the third planet in the Tau Ceti system, located approximately 11.9 light-years from Earth. Alustien is a gas giant with a diameter of about 130,000 kilometers, making it larger than Jupiter. The planet is notable for its extensive ring system, which is composed of ice and rock particles, and its numerous moons.

The most significant moon of Alustien is Eros, which is home to a human colony. Eros is a rocky body with a diameter of about 1,000 kilometers and is tidally locked to Alustien, meaning it always presents the same face to the planet. The colony on Eros is a research outpost dedicated to studying the planet and its moons, as well as conducting scientific experiments in the low-gravity environment.

Alustien's ring system and moons have been the subject of much scientific interest, as they provide a unique opportunity to study the formation and evolution of planetary systems. The planet's extensive ring system is believed to be the result of a collision between two moons, while the moons themselves are thought to have formed from the debris of that collision.

In addition to its scientific significance, Alustien is also of strategic importance due to its location in the Tau Ceti system. The planet is a key waypoint for ships traveling between Earth and the Belt, and its moons provide a valuable source of resources for the human colonies in the system.