The Snow Biome is a biome mostly made out of ice, slush, and snow. It tends to often snow in these biomes. Snow Biomes also tend to have pools of purple water inside of them, and sometimes Snowmen are able to spawn in these biomes. On occasion, it's possible for igloos to spawn. Contrary to expectations, low-level 'snow' planets don't actually harness much value; obtaining protective gear to survive in snow biomes does not come early game, it is likely you will be past Tier 1 by the time you do have the protective gear, so there isn't much point exploring in snow biome-covered planets in the Alpha sector.