Kerbal Star Systems Wiki

Cyln is the last and coldest planet in the Kelnis System. It is the only planet in the system that is entirely covered in ice.

In-game Description

"Cyln is like a recently made ice cream scoop. It’s a little warm on one side from the sun, but nowhere near enough to melt it. Cyln is entirely covered with a sheet of ice, and although the ice on the dayside may be a little thinner, it is still entirely a snowball planet. Don’t forget to pack those hand warmers!"

Physical Characteristics

Cyln is the smallest planet in the Kelnis System (slightly smaller than Irke), and also the coldest too. Cyln's surface is covered entirely in packed sheets of ice. Unlike all the other planets except Hilio, Cyln is believed to have never been able to host liquid water on the surface. However, some scientists think that tidal forces from Kelnis combined with radiation from the core could form a small subsurface ocean on Cyln. The only way to find out is to visit Cyln yourself!


Cyln's atmosphere is composed mostly of nitrogen (N₂), with smaller amounts of hydrogen (H₂) and methane (CH₄). Scientists believe that due to the fact that Cyln still retains decent amounts of lighter gases on the surface Cyln could have a magnetosphere shielding it from solar wind from Kelnis, which also is proof of a molten core.


Cyln Biome.png

  • Fractures
  • Chaos Terrain
  • Icy Midlands
  • Icy Highlands