Eta Cassiopeia System

The ETA Cassiopeia System is a human-controlled star system within the Orion Arm of the Milkyway Galaxy. It consists of six terrestrial planets, one gas giant, and 79 moons. ETA Cassiopeia System is an Inner Colony system of the United Nations Federation located about 1.20 AU (19 light-years) from Sol.

1. Cassiopeia I, or Cassiopeia Prime, is a barren rocky planet similar to Mercury in the Sol System. Its surface is a vast desert of heat-blasted rock, crisscrossed with deep canyons and towering cliffs. Despite its inhospitable environment, numerous mining outposts dot the surface.

2. Eden, also known as Cassiopeia II, is a ‘green zone’ earth-like planet and the capital world of the system with an estimated population of 47.8 million. Eden boasts verdant groves, pristine oceans, and a bustling metropolis that serves as the cultural and economic hub of the ETA Cassiopeia System.

3. Helios, or Cassiopeia III, is a hostile Mars-like world with extreme temperatures and frequent sandstorms. The only settlements are mining and research outposts hardened against the harsh conditions.

4. Tartarus, also known as Cassiopeia IV, is a volcanic world covered in molten lava and toxic gases. Its surface is constantly shifting due to tectonic activity, making it too dangerous for ground colonization. However, resource extraction companies have established small outposts to harvest the planet's valuable minerals.

 

5. Atlas, or Cassiopeia V, is a frozen world with a thick layer of ice and snow covering its surface. Despite its freezing temperatures and low gravity, Atlas has a surprisingly diverse ecosystem of plant-life across its surface.

6. Eisheim, known as Cassiopeia VI, is the second-farthest planet from the star in the ETA Cassiopeia System. As a result, it has an extremely cold environment with strong winds and frozen landscapes. The planet's atmosphere is also highly toxic.

7. Hyperion, or Cassiopeia VII, is the largest planet in the ETA Cassiopeia System, with a diameter of over 58,000 kilometers. It has a distinctive blue and green coloration due to its thick atmosphere, which is primarily made up of gas and ice.   Hyperion's strong gravitational pull also contributes to its unique appearance. The intense pressure at the planet's core causes layers of liquid metallic hydrogen to form, giving the planet its characteristic bands and swirls. Hyperion also has many moons orbiting it, with 62 confirmed moons. These moons range from small icy bodies to large rocky worlds.