Forscan I is one of the largest planets of the Forscan system, second only to the gas giant Forscan III. It is frigid, with almost half of the surface covered with a thick layer of ice, and the rest is rocky terrain. The planet's atmosphere is composed mainly of hydrogen and helium, with small amounts of other gases. The presence of ammonia in a relatively high percentage makes the atmosphere toxic. With all these harsh conditions, it is no surprise that the planet's sentients are required to use breathing masks to curtail the toxicity. Forscan I's peculiar atmosphere blocks much of the light from the system's star, maintaining the icy climate despite its proximity to the sun.

Forscan I's gravity levels are much lower than what might be expected for a planet of its size. Researchers hypothesize that the planet has a hollow core, lowering its mass and therefore its gravity. Geological scans support the theory, but because the thickness of the crust is believed to be at least half of the planet's radius, the inner core has not been accessed for study. Prospectors have identified signs of several valuable minerals, but Tresarian authorities are still weighing the costs of mining operations in such a toxic atmosphere.