Altair II

Altair II, also known as Veltrass, is an arid Inner Colony world of Humanity within the Altair System of the Orion Arm of the Milkyway Galaxy. Altair II experiences extreme temperature fluctuations between its day and night cycles. There are a few hardy species of plants and animals that have adapted to these harsh conditions. Some United Nations Federation research domed-outposts are scattered across the planet to study the unique lifeforms and weather patterns.

Altair II features a predominantly arid and rocky terrain marked by expansive salt flats, wind-eroded mesas, and shallow basins that once held water in the planet’s ancient past. The landscape is dominated by scorched highlands in the equatorial region, shifting dune seas in the western hemisphere, and deep canyon systems etched by long-vanished surface flows. The southern hemisphere contains the Valtrun Expanse, a plateau rich in iron oxides and known for its vivid red-orange soil.   Tectonic activity is minor but still present, especially along the Marnel Rift, a fault line spanning 2,700 km that occasionally experiences low-magnitude quakes. No active volcanism exists, but extinct shield volcanoes and long-collapsed calderas are scattered across the mid-latitudes. Geological dating suggests widespread volcanic activity ended over 1.3 billion years ago, after which erosion and sedimentation became dominant forces shaping the surface. Crustal analysis indicates that large-scale mantle convection ceased early in the planet's history, with remaining tectonic stress concentrated in narrow zones of crustal weakness. To the north, the Kelvar Crater Complex comprises a dense cluster of impact structures dating back to a heavy bombardment phase approximately 3.9 billion years ago. These craters, some spanning over 100 km in diameter, have become key study zones for astrogeology and early planetary development. The surrounding region contains high concentrations of ejecta-formed breccia and naturally vitrified rock.   The eastern hemisphere contains the Tarsil Chasmata, a rift-valley system nearly 1,600 km long and up to 7 km deep, believed to have formed through crustal collapse after subsurface magma withdrawal. Its walls reveal stratified mineral layering, including hydrated salts and compacted ash deposits, indicating a complex geologic history involving episodic aqueous activity. Subsurface imaging and drilling efforts have confirmed the presence of multiple brine aquifers locked beneath compacted regolith layers at depths between 80 and 140 meters. These aquifers are patchy and unstable but serve as critical ecological zones supporting limited biological activity. Surrounding these underground reserves are high-salinity crusts and mineralized soil matrices containing halite, sylvite, and perchlorates—chemistries that may be relics of a formerly more temperate and hydrologically active era. Altair II's polar regions are dominated by regolith-covered rocky plains with scattered ice-encrusted boulders, though no permanent surface ice exists. Seasonal subsurface frost accumulation occurs at high latitudes, detectable via orbital spectrometry and ground-penetrating radar, though it sublimates rapidly during the warm season.

Altair II experiences dramatic temperature fluctuations due to its thin cloud cover, low humidity, and moderately dense atmosphere. Daytime surface temperatures in equatorial zones often reach 46°C (114.8°F) under direct solar exposure, while nighttime lows in desert basins and high-altitude regions regularly drop to -68°C (-90.4°F). This diurnal variation is intensified by the planet’s 56.8-hour sidereal day, which results in extended periods of solar heating followed by equally long cooling phases, allowing surface temperatures to change drastically across the course of a single rotation.   Altair II’s atmosphere, composed primarily of nitrogen (76.8%) and carbon dioxide (14.2%), with secondary contributions from argon and oxygen, provides limited thermal buffering. While sufficient to retain some heat during the planetary night, the low water vapor content and low overall humidity result in poor heat retention efficiency, leading to rapid radiative cooling during twilight and darkness. Heat loss primarily occurs through longwave infrared radiation, unimpeded by cloud cover or insulating greenhouse gases. Altair II’s 24.9° axial tilt produces marked seasonal changes in temperature and sunlight distribution, comparable in strength to Earth’s. During the planet’s 322.5-day orbit, the hemispheres alternately receive increased solar flux, leading to warm and cold seasons in both hemispheres. Seasonal thermal expansion and contraction of the upper soil layers cause cyclic mechanical stress on the terrain, contributing to gradual terrain fracturing and rock exfoliation, particularly in sedimentary and volcanic regions. Surface wind patterns are driven by daytime convective heating and nighttime subsidence. These thermal differentials generate moderate to strong ground-level winds in open desert regions, especially during sunrise and sunset transitions. Wind velocities regularly exceed 90 km/h during peak shifts and can reach 140 km/h in storm-prone regions near the perihelion phase of the orbit. These winds mobilize fine dust and mineral particulates, contributing to regional erosion and short-duration sandstorms, though these events are infrequent and typically limited in scope.   Atmospheric pressure at sea level remains stable at 104.1 kPa (1.027 atm), enabling human presence with standard protective gear but not requiring full pressure suits. However, the presence of 14.2% carbon dioxide and low oxygen volume (4.3%) renders the atmosphere unbreathable without respiratory filtration or oxygen supplementation. The elevated CO₂ levels also increase the efficiency of certain photosynthetic plant analogs, particularly C4-type and CAM-like metabolic flora adapted to low-oxygen environments. Fog formation occurs under specific microclimatic conditions—mainly in crater basins, low-lying terrain, and aquifer-fed oases—when nocturnal radiative cooling causes ambient air to reach dew point. These fogs are typically short-lived and limited in coverage, but they provide vital hydration for localized ecosystems. Radiation levels at the surface are elevated compared to Earth due to the planet's weak magnetospheric shielding and lower atmospheric mass. The surface absorbed dose rate averages 89 μGy/h, while the equivalent dose rate is 104 μSv/h, levels which are non-lethal but require exposure management for long-term habitation. These radiation levels are relatively stable but may increase during stellar activity from Altair, including flare events and solar particle emissions, necessitating temporary withdrawal to shielded habitats.   There is no precipitation in the conventional sense—no rainfall, snowfall, or hail—due to the near-absence of a functioning hydrological cycle. Trace atmospheric moisture exists in the form of high-altitude ice crystals or localized fogs, but no cloud systems capable of producing precipitation are present. Humidity levels average below 5% in most regions, with slightly higher concentrations near brine seep zones and seasonal fog basins.

Altair II sustains a surprisingly resilient and ecologically diverse biosphere, shaped by its extreme diurnal temperature shifts and mineral-rich environment. The fauna are highly specialized, with most species exhibiting adaptive features for thermoregulation, desiccation resistance, and carbon dioxide tolerance. Native animal life is primarily terrestrial, with species clustering around subsurface aquifers and brine seepage zones. These zones act as biological oases, where complex food webs have evolved independently across isolated bioregions.   Common animal species are predominantly endothermic, burrow-adapted, and exhibit advanced respiratory systems capable of filtering low oxygen concentrations while metabolizing trace organics from mineral-rich soil. One well-documented class of wildlife includes the Kreval species group—small, muscular vertebrates with layered dermal plates composed of silicate-carbon composites. These creatures use internal microvascular heat-exchange systems to survive sharp thermal gradients during dusk and dawn transitions. Predatory species, such as those classified within the Serravor genus, are equipped with elongated olfactory lobes and mineral-hardened bite structures, allowing them to hunt burrowed or partially exhumed prey in hard-packed soil. These carnivores often rely on seismic sensing organs to detect movement, and some demonstrate rudimentary group hunting behavior in brine-fed valleys. No known species exhibit flight capabilities, though gliding and leaping adaptations have been observed in canyon-dwelling populations.   Altair II's flora, while less abundant, is highly efficient in moisture retention and photosynthetic conversion under high-irradiance conditions. Vegetation tends to grow laterally along rocky surfaces or in fissure zones where microclimates offer protection from radiative overexposure. Dominant plant forms include Kerraliths, which are deep-rooted stalk plants with calcified outer tissues and internal silica gel networks that slow evapotranspiration. Their photosynthetic process is modified to operate optimally in the red-shifted light wavelengths of late afternoon, minimizing thermal stress. Smaller flora species, such as Varra sponges and Filament mosses, thrive near subcrustal water vapor vents and cave entrances. These organisms often function as biological anchors for symbiotic microbial colonies and serve as the base of localized food chains. Several of these species exhibit protective pigments or microcrystalline outer layers to deflect solar UV radiation, a critical adaptation on a world where atmospheric scattering is minimal.   Though the biosphere is fragmented and localized, genetic sampling indicates significant diversification between isolated populations, suggesting millions of years of evolutionary development under extreme selective pressures. Human xenobiologists continue to monitor these ecosystems for novel metabolic pathways, extremophile enzymes, and bioadaptive behaviors useful in terraforming and medical applications. Strict containment and sterilization procedures are enforced to avoid ecological disruption or offworld contamination.

Altair II is orbited by a single natural satellite, Veltrass Minor, with a diameter of 1,042 km and an orbital period of 41.5 days. The moon follows a slightly eccentric and inclined prograde orbit approximately 238,000 km from the planetary surface. It is believed to be a captured celestial body—likely a large asteroid from the Altair System’s early formation period—due to its irregular, ellipsoidal shape and non-uniform internal density. Its composition includes a mixture of silicate rock, nickel-iron deposits, and trace volatile elements locked within deep subsurface layers. Veltrass Minor’s surface is heavily cratered, with no signs of tectonic activity, internal heating, or cryovolcanism. The regolith is loosely compacted and rich in micrometeorite impact glass, with large surface fissures extending across its southern hemisphere. These fissures are theorized to have formed during gravitational interactions during its initial orbital stabilization period.   Veltrass Minor lacks any meaningful atmosphere and has no magnetosphere, exposing its surface directly to solar and cosmic radiation. Surface gravity is weak, at approximately 0.18 m/s², limiting any natural ability to retain volatiles or develop erosion cycles. However, this low gravity makes Veltrass Minor a candidate for lightweight infrastructure and automated orbital support platforms. Although inert and uninhabitable, Veltrass Minor exerts measurable tidal influences on Altair II, contributing to minor crustal flexing and the stimulation of brine migration in certain aquifer zones. These tidal forces are strongest when the moon is at perigee and aligned with Altair II’s perihelion, leading to increased seismic readings in the Velkari Basin and other tectonically active fault zones.   UNF planetary monitoring systems include long-range sensors placed in synchronous orbit near Veltrass Minor to triangulate surface activity and provide early warnings for dust storms and radiation surges. While no permanent installations currently exist on the moon, exploratory probes have identified several regions with stable bedrock and low dust drift, suitable for future landers or potential relay platforms. Ongoing feasibility studies are exploring the use of Veltrass Minor as a staging ground for higher-orbit satellite arrays and planetary defense radar systems.