Tara-4

Tara-4 is the fourth innermost planet in the Tara system and a Class 1 garden world with two small satellites, barely larger than asteroids. Tara-4 has copious amounts of water on the surface, but most is frozen, with the only liquid water located around the equator. The atmosphere is breathable and thin (but of survivable pressure) and primarily composed of Oxygen with very high concentrstions of Xenon, rendering it a very poor insulating layer. The global average temperature is around 110-130K, with the average temperature in settled areas being around 170-200K. Its population is around 375,000. By far the most populous settlement is Cryoton, also the planetary capital, with 260,000 residents. The primary industry is the extraction D-Metals.

Biology
Tara-4 has a somewhat nonstandard biological makeup. On the prokaryotic level, all is normal, as well as very simpler eukaryotes. However, upon reaching the level of evolution of vertebrates, things become unusual. Due to the very cold temperatures, all animals are warm-blooded. This, in turn, resulted in two size extremes. The 'middle ground' between these two extremes has very few known species. All those that are known live near deep sea vents, or any other significant heat source. Terrestrial plant life primarily consists of grasses and shrub analogues. Rather than chlorophyll, most plants use a variety on cartenoids to absorb solar energy. As cartenoids cannot actually photosynthesize, some chlorophyll is retained so as to allow for photosynthesis.