Asterra System

Asterra Star System

The Asterra star system is dynamically stable and long-settled. Most permanent infrastructure predates the loss of Ytharia and was designed for extended autonomous operation.

Asterra (Primary Star)

Type	G-type main sequence
Mass	0.93 Sol
Luminosity	0.78 Sol
Radius	0.95 Sol
Estimated age	~7.1 billion years
Stellar activity	Low flare rate
Habitable zone	0.62–0.74 AU

Companion Star — Carmyn

Carmyn (Companion Star)

Type	M-type red dwarf
Mass	0.31 Sol
Luminosity	0.012 Sol
Radius	0.34 Sol
Separation	~1,400 AU
Orbital period	~28,000 years
Stellar activity	Moderate flare rate
Planets	3

Carmyn is the red companion star of the Asterra binary system, orbiting at a wide separation that renders it a naked-eye fixture in Ytharia's night sky — a dim but constant red point, distinct from the stars of the broader field. Its slow drift across centuries of recorded observation made it a cultural and navigational reference point long before its stellar nature was understood.

Among the Alf, Carmyn held deep folkloric significance. It was variously interpreted as a wayward sun, a warning light, or an ancestral hearth — depending on the cultural tradition. Its position in the sky was used to mark seasonal transitions and appeared in the foundational texts of several Ytharian traditions.

“	"The red star does not rise. It waits."	”
	— Common Alf proverb, origin uncertain

Carmyn hosts three planets of its own, none of which were inhabited or substantially developed prior to the loss of Ytharia. Its position in the system has since taken on renewed significance as a navigational waypoint for Project Exodus planning.

C-1. Vethara

Vethara

Type	Venusian (terrestrial)
Orbital radius	0.08 AU (Carmyn)
Orbital period	~18 standard days
Mass	0.81 Earth
Surface gravity	0.88 g
Atmosphere	~62 bar, CO₂-dense
Mean surface temp	~720 K
Axial tilt	3.1°
Moons	None

Vethara is a dense, hot terrestrial world locked in a runaway greenhouse state. Its thick carbon dioxide atmosphere traps heat from Carmyn's close proximity, producing surface temperatures hostile to any known form of life. The planet's surface is geologically active, with widespread volcanic plains and a near-permanent sulphur haze layer visible from orbit.

Vethara was surveyed but never developed. It holds no strategic value beyond its role as an orbital reference marker for approach to the Carmyn system.

C-2. Pelun

Pelun

Type	Dwarf world
Orbital radius	0.41 AU (Carmyn)
Orbital period	~194 standard days
Mass	0.018 Earth
Radius	~1,140 km
Surface gravity	0.21 g
Atmosphere	Trace only
Mean surface temp	~145 K
Moons	1 (minor)

Pelun is a small, heavily cratered dwarf world with minimal gravity and no retained atmosphere to speak of. Its surface is ancient and largely undisturbed — a record of early system bombardment preserved in ice and regolith. A single irregular moonlet, likely a captured body, orbits at close range.

Pelun's low gravity and stable orbit have made it a theoretical candidate for a low-cost resupply cache or fuel staging depot in long-range Exodus planning — though no infrastructure has been established.

C-3. Dorryn

Dorryn

Type	Cold gas giant
Orbital radius	4.8 AU (Carmyn)
Orbital period	~38 standard years
Mass	0.6 Jupiter
Radius	~0.88 Jupiter
Mean temp	~52 K
Atmosphere	H₂/He, deep methane layer
Ring system	Faint, narrow
Moons	17 confirmed

Dorryn is a cold, methane-tinged gas giant occupying the far reaches of the Carmyn system. It receives very little energy from either star and sits in a state of deep atmospheric calm compared to the inner gas giants of the primary system. Its blue-grey coloration — caused by methane absorption of red wavelengths — makes it visually distinct from Vael, Orthis, or Ceryn.

Several of Dorryn's larger moons show subsurface liquid potential, though none have been explored in any meaningful depth. The planet's remote position and the system's general inaccessibility prior to the invasion meant Dorryn remained essentially unknown territory at the time of Ytharia's fall.

System Scale

• Inner system boundary: ~0.1 AU
• Primary asteroid belts: 2.4 AU and 6.8 AU
• Outer planetary boundary (Helior): ~38 AU
• Effective heliopause influence: ~95 AU
• Carmyn separation: ~1,400 AU

Traffic followed fixed corridors enforced by orbital control infrastructure. Carmyn's wide separation placed it outside routine system traffic but within long-range communication range.

Planetary Order — Primary System

1. Keth

Keth

Type	Rocky (terrestrial)
Orbital radius	0.21 AU
Orbital period	41 standard days
Rotation	Tidally locked
Mass	0.62 Earth
Surface gravity	0.78 g
Atmosphere	~0.2 bar, volatile-poor
Mean dayside temp	~620 K
Mean nightside temp	~190 K
Moons	None

Keth exhibits permanent hemispheric contrast. The dayside is exposed to continuous stellar radiation. The nightside remains cold and shielded.

Keth was never intended for habitation and functioned solely as an inner-system industrial node.

Keth Mining Operations

Mining activity was restricted to the nightside.

• Operational depth: 300–1,200 m
• Facilities: Subsurface, hardened
• Automation level: High
• Permanent staffing (peak): <400 system-wide
• Power: Orbital solar collectors and compact reactors

2. Ytharia

Ytharia

Type	Rocky (ocean-dominated terrestrial)
Orbital radius	0.68 AU
Orbital period	286 standard days
Axial tilt	18.4°
Mass	1.08 Earth
Surface gravity	1.02 g
Surface water coverage	~72%
Mean surface temp	~284 K
Atmosphere	~1.4 bar, moisture-rich
Moons	Two (Elaris, Tirien)

Ytharia was the only planet in the Asterra system known to support complex native life and the historical and cultural origin point of the Alf people.

Ytharia Orbital Station

A major orbital station operated in high orbit.

• Orbital altitude: ~42,000 km
• Primary ring diameter: ~11 km
• Permanent population (pre-loss): ~180,000
• Berths: ~10 capital-class vessels

The station functioned as the primary spaceport, customs hub, manufacturing center, and traffic control node for the system.

Moons of Ytharia

Elaris

Elaris (Major Moon)

Radius	~1,720 km
Mass	0.94 Luna
Orbital distance	~410,000 km
Orbital period	34.6 days
Base capacity	~25,000

Elaris governed Ytharia's primary tidal cycles and stabilized axial tilt. Low seismic activity enabled long-duration operations and sensitive instrumentation.

Elaris Lunar Base

• Population capacity: ~25,000
• Launch mass throughput: ~4.2 million tons per year
• Primary functions: deep-space observation, orbital traffic support, system monitoring

Tirien

Tirien (Minor Moon)

Radius	~720 km
Orbital distance	~610,000 km
Orbital period	69.2 days
Orbital resonance	2:1 with Elaris
Inclination	3.1°

From Ytharia's surface, Tirien was frequently occluded by Elaris and visible only during specific alignments.

3. Vael

Vael

Type	Gas giant
Orbital radius	3.1 AU
Orbital period	5.4 years
Mass	1.7 Jupiter
Magnetosphere radius	~9 million km
Moons	40+ confirmed

Vael's magnetosphere deflected a significant fraction of cometary and interstellar debris, contributing to inner-system stability.

4. Orthis

Orthis

Type	Gas giant
Orbital radius	7.6 AU
Orbital period	20.9 years
Mass	1.2 Jupiter
Ring radius	~140,000 km
Moons	30+

Several moons show evidence of subsurface oceans or cryovolcanic activity.

Orthis Orbital Station

• Orbital altitude: ~1.8 million km
• Population (peak): ~95,000
• Annual material throughput: ~120 million tons

The station served as the primary logistical hub for asteroid and moon mining operations in the middle system.

5. Ceryn

Ceryn

Type	Gas giant
Orbital radius	14.2 AU
Orbital period	53.6 years
Mass	0.7 Jupiter
Moons	45+ (irregular, partially captured)

Orbital characteristics indicate a major disruption event approximately 1.3 billion years ago, likely responsible for Ceryn's irregular and partially captured moon population.

6. Helior

Helior

Type	Gas giant
Orbital radius	38 AU
Orbital period	~235 years
Mass	0.4 Jupiter
Moons	10+ (sparse, frozen satellites)

Helior marks the outer boundary of significant planetary mass in the primary system.

7. Nysa

Nysa

Type	Rocky (cold terrestrial)
Orbital radius	62 AU
Orbital period	~490 years
Mass	0.31 Earth
Surface gravity	0.55 g
Atmosphere	<0.1 bar, frozen trace gases
Mean surface temp	~35 K
Moons	None

A frozen, isolated world at the far edge of the primary system. The lack of satellites is attributed to early orbital instability and gravitational interference from the outer gas giants.

Canon Status

The Asterra system no longer shows any signs of life. All infrastructure is inactive — no power, no supply lines, no personnel. Ytharia, once the system's historical and cultural heart, is now inhospitable and war-torn. Carmyn remains a navigational reference point for Project Exodus planning.