Star types

This page is a Work in Progress as much of the lore/Development for the game is yet to be established.

Star Types

Starship Simulator features a diverse range of star types within its procedurally generated Milky Way galaxy, based on the real-world stellar classification system and astrophysical principles. The type of star significantly influences the formation, characteristics, and potential habitability of its surrounding planetary system. The game generates main sequence stars (O, B, A, F, G, K, M), brown dwarfs (L, T, Y), and stellar remnants (White Dwarfs, Neutron Stars, Black Holes). Groundwork for other types like T-Tauri and Wolf-Rayet stars has also been implemented.

Stellar Classification

The game uses the standard OBAFGKM spectral sequence for main-sequence stars, ordered from hottest to coolest, along with L, T, and Y classes for brown dwarfs. Development Build 0.225.0.30 introduced support for 80 stellar sub-classes, ranging from O0V (~50,000 K) down to Y9 (~250 K).

Main Sequence Stars

These are stars actively fusing hydrogen into helium in their cores.

O-Type

• Colour: Blue-Violet
• Temperature: > 30,000 K (O0V ~50,000 K)
• Characteristics: Extremely hot, luminous, massive, and short-lived. Very rare.
• Location: Primarily found in star-forming regions (Open Clusters) within the Thin Disc's spiral arms.
• System Notes: Due to high radiation and short lifespan, complex life is unlikely. Planets may be fewer or primarily gas giants; rocky planets would lack heavier elements if formed early (Population II).

B-Type

• Colour: Blue-White
• Temperature: 10,000 K - 30,000 K
• Characteristics: Very hot, luminous, massive, relatively short-lived. Rare.
• Location: Mostly found in the Thin Disc's spiral arms, often near O-type stars or in young clusters.
• System Notes: Intense radiation makes surface habitability difficult close-in.

A-Type

• Colour: White
• Temperature: 7,500 K - 10,000 K
• Characteristics: Hot, bright stars. More common than O or B types.
• Location: Common in the Thin Disc.
• System Notes: Habitable Zone further out than G-type stars.

F-Type

• Colour: Yellow-White
• Temperature: 6,000 K - 7,500 K
• Characteristics: Slightly hotter and more massive than Sol. Common.
• Location: Widely found in the Thin Disc.
• System Notes: Good candidates for finding potentially habitable worlds.

G-Type

• Colour: Yellow
• Temperature: 5,000 K - 6,000 K
• Characteristics: Stable, long-lived stars like Earth's Sol (a G2V type). Common.
• Location: Abundant throughout the Thin Disc.
• System Notes: Considered prime candidates for hosting Earth-like planets within their well-defined Habitable Zone.

K-Type

• Colour: Orange
• Temperature: 3,500 K - 5,000 K
• Characteristics: Cooler, less massive, and longer-lived than G-type stars. Very common.
• Location: Very common throughout the galaxy, including older regions.
• System Notes: Habitable Zone is closer to the star. Long lifespan provides ample time for potential life development, though planets may experience tidal locking more frequently.

M-Type

• Colour: Red-Orange
• Temperature: < 3,500 K
• Characteristics: Red dwarfs. The most common type of star in the Milky Way (~76%). Cool, dim, very low mass, extremely long-lived.
• Location: Ubiquitous across all galactic regions.
• System Notes: Habitable Zone is very close to the star, increasing risk of tidal locking and stellar flare activity impacting habitability. Developer notes mention their visual brightness from the Bridge window has been toned down for realism.

Brown Dwarfs

Sub-stellar objects not massive enough to sustain hydrogen fusion like main sequence stars. They bridge the gap between giant planets and small stars. Groundwork added in Build 0.225.0.16, implementation in Build 0.225.0.25.

L-Type

• Temperature: ~1,300 K - ~2,400 K
• Characteristics: Hotter than planets, cooler than M-type stars. Emit mostly infrared light.
• Notes: Too dim to be easily visible from the Bridge window (Build 0.225.0.66). Holo display colour clamped to avoid appearing too bright (Build 0.225.0.49).

T-Type

• Temperature: ~700 K - ~1,300 K
• Characteristics: Cooler still, with methane prominent in their atmospheres. Sometimes exhibit a magenta tint in-game (Build 0.225.0.26).
• Notes: As L-Type, low visibility and adjusted holo display colour.

Y-Type

• Temperature: < ~700 K (down to ~250 K for Y9)
• Characteristics: The coolest category, extremely dim, essentially planetary mass objects radiating residual heat.
• Notes: As L/T-Type, very low visibility and adjusted holo display colour.

Stellar Remnants

The end-points of stellar evolution for different types of stars.

White Dwarf

• Characteristics: The dense, hot core left behind by a low-to-medium mass star (like Sol) after it exhausts its nuclear fuel and sheds its outer layers. Gradually cools over billions of years.
• Notes: Data for ~2 million real white dwarfs within 2000 LY of Sol added in Build 0.225.0.27.

Neutron Star

• Characteristics: Extremely dense object composed primarily of neutrons, formed from the supernova explosion of a massive star (too small to form a black hole). Often rotate rapidly (pulsars).
• Notes: Groundwork for implementation added in Build 0.225.0.16.

Black Hole

• Characteristics: A region of spacetime where gravity is so strong that nothing, not even light, can escape. Formed from the collapse of very massive stars or through other processes (like galactic cores).
• Notes: Groundwork added (Build 0.225.0.16). Sagittarius A* placed at (0,0,0). Behaviour refined (mass range, radii) and planets added (tend to be icy due to large Roche limits) in Build 0.225.0.31. Holo display rendering size fixed (Build 0.225.0.44).

Other Types

Groundwork has been laid for additional stellar or sub-stellar objects:

• T-Tauri Stars: Very young stars still in the process of gravitational contraction, before reaching the main sequence.
• Wolf-Rayet Stars: Massive, very hot stars rapidly losing mass via strong stellar winds.
• Rogue Planets: Planetary-mass objects not gravitationally bound to any star, drifting through interstellar space.

In-Game Significance

A star's type directly impacts:

• Visuals: The appearance and colour of the star from space and on the Sensors/Holo-display. Sensor UI elements reflect star colour based on Kelvin temperature (Build 0.225.0.45). Spectral analysis graphics available (Build 0.225.0.64).
• System Generation: Influences the type and distribution of planets likely to form (e.g., metallicity based on star population type, likelihood of rocky vs gas planets).
• Habitable Zone: Determines the location and size of the region where liquid water might exist.
• Navigation: Star types may influence FTL travel or generate specific hazards (e.g., high radiation near O/B stars, gravitational effects near remnants).