Tryast is a treacherous world of icy bogs. The atmosphere content is not unlike that of Coruscant, however, the abundant presence of radon, emitted from the bogs, makes the air lethal for most living beings. Most of Tryast’s swamps are frozen in ice for a few millions of years now due to Tryast’s outward orbit. Tryast does not follow a perfect orbit around the sun; instead, it moves a couple of centimeters toward the rim of the star system. As it slowly moves outwards, the average temperature of the planet drops slightly, and over the many years, the swamps slowly become frozen in the winters and never thaw again. There are a number of dry highlands in the form of barren rock formations. They stick out from the icy bogs and are a useful tool for scientists to understand the effects of the lowering of temperature, as these stone formations record many properties of each age of this planet.

On the coast of the equatorial sea, the only large body of water on Tryast, a seemingly eternally active volcano creates a breathtaking sight. The volcano opening pumps out a few hundred liters of molten lava per day that slowly travels down the side of the mountain towards the sea. When the lava makes contact with the seawater, the lava is cooled as it slowly moves toward the bottom of the sea. The process has been going since humans, Corellians specifically, first explored this world countless generations ago. The seawater in this region is actually warm to the touch from this process.

Because radon is a heavy gas, it sits close to the surface, and a lot of the radon is absorbed into the seawater. As a result, there is nearly no life under the seawater either. Deep-sea explorers find the underwater scenery of Tryast to be dull and barren, often reporting the scenery to be darkly eerie. In the bogs, however, some vegetation can be found, along with a small number of insect varieties. They, of course, are not harmed by the radon gas. Plant and insect life are limited to the not-yet-frozen terrain near the equator only.