planetbäraren

Planetbäraren is a fictional planet described in Swedish-language science fiction and in educational materials about exoplanets. It orbits a sun-like G-type star in the imagined star system Lumen, roughly 120 light-years from Earth in the cited literature. The name derives from the Swedish word for bearer, reflecting its role as a centerpiece in speculative narratives about life-bearing worlds.

Planetbäraren is classified as a rocky super-Earth. It has a radius of about 1.4 times that of Earth and a mass near 3 Earth masses, yielding a surface gravity around 1.5 g. The density and composition suggest a predominantly rocky interior with a substantial silicate mantle and a modest iron core. The planet completes a rotation in roughly 24 hours and possesses a modest axial tilt of about 15 degrees, allowing seasonal variation.

The orbit places it at about 0.95 AU from its star, with a near-circular trajectory (eccentricity ~0.05). The orbital period is roughly 330–340 days. A substantial ocean cover is assumed, amounting to about 40–60% of the surface, which together with a moderate greenhouse effect yields mean surface temperatures in the range conducive to liquid water.

The atmosphere is envisioned as nitrogen-rich with carbon dioxide and trace amounts of water vapor; the greenhouse effect is moderate, and a magnetic field is assumed to protect the atmosphere from stellar wind. Planetbäraren is used in teaching to illustrate how transit and radial-velocity data can constrain size, mass, and atmospheric prospects in habitable-zone worlds, and it appears in several fictional tomes and course materials.