THE DEFINITIVE INTERSTELLAR EXPANSION FOR KERBAL SPACE PROGRAM.
Time to find out if your staging works at light-year scale.
You have mapped the Mun, left a trail of rover wreckage across Duna, and somehow brought your Jool exploration crews home with most of their structural integrity intact. Your launch pads are scorched down to bedrock, your VAB floor is permanently stained with hypergolic sludge, and you have memorized every single orbital anomaly in the stock system.
That was just the warm-up.
Kerbal Star Systems 2 (KSS2) expands Kerbal Space Program into a sprawling, multi-star interstellar sandbox. Forget short burns, quick returns, and standard chemical lifters. You are now tasked with engineering colossal generation ships, stringing deep-space relay networks across light-years, and calculating multi-year orbital insertions across six entirely original stellar systems.
Keep your reactors shielded, your life-support margins positive, and your relative velocity well below "vaporizing on impact."
Preferably all three. Though if you only manage two, mission control will happily settle for a clean screenshot before the telemetry cuts out entirely.
Modding KSP at a galactic scale is an exercise in gentle domestic terrorism against the Unity engine. KSS2 is the battle-tested result of an interstellar development journey that began all the way back in 2015.
| Era | Project | Engineering Milestone |
|---|---|---|
| 2015–2019 | Kerbal Star Systems (KSS1) |
The vanguard. Proved to a skeptical community that multi-star architectures could run inside KSP without instantly tearing the universe apart. |
| 2019–2024 | Galaxies Unbound (GU) |
The expansion phase. Pushed modular system design, custom resource distribution, and deep mechanical frameworks to their absolute limits. |
| Today | Kerbal Star Systems 2 (KSS2) |
The apex. A clean-sheet architectural rebuild integrating modern volumetric visual standards, optimized memory handling, and ruthless balance. |
KSS2 is not a casual touch-up of past work. It is a ground-up reconstruction shaped by ten years of discovering what works, what breaks the physics engine, and what belongs back in the R&D recycling bin.
Set navigation coordinates far beyond Eeloo. KSS2 introduces six completely distinct stellar environments, each structured around its own astrophysical class, climate profile, and logistical challenge.
| Star System | Classification | Environmental Profile & Mission Focus | Status |
|---|---|---|---|
| Aethera | Compact Red Dwarf |
Tightly packed worlds bathed in the aggressive radiation of violent stellar flares. Your primary interstellar testing ground. | RELEASED |
| Nova Kirbani | Multiple-Star System |
A sprawling, multi-body frontier demanding heavy orbital infrastructure beneath the combined glare of three suns. | RELEASED |
| Kormin | Brown Dwarf |
A dark, chemically exotic sub-stellar cluster orbiting a failed star. Bring heavy illumination and thermal insulation. | RELEASED |
| Kerr | Galactic-Center Black Hole |
The abyss. Extreme gravity wells, relativistic time dilation, and blinding accretion phenomena. The absolute endgame challenge. | RELEASED |
| Seereon | Brilliant Star + Companion |
Searing high-energy environments engineered to stress-test the thermal limits of established late-game programs. | EXPANDING |
| Orbel | Evolved Giant Star |
Ancient planets and shattered moons scorched by the violent, unstable closing chapters of stellar evolution. | EXPANDING |
- Pandor Expansion: A lush, bioluminescent moon orbiting a gas giant within Nova Kirbani. Prime real estate for scientific outposts and ambitious permanent colonization.
- Red Blalo Expansion: An alternate planetary configuration featuring heavily oxidized terrain, deep crimson oceans, and a radically hostile biosphere.
View Astronomical Inspirations (Click to expand)
| KSS2 System | Real-World Astronomical Parallel |
|---|---|
| Aethera | TRAPPIST-1 |
| Nova Kirbani | Alpha Centauri A, Alpha Centauri B, and Proxima Centauri |
| Kormin | Luhman 16 |
| Seereon | Sirius |
| Orbel | Pollux |
| Kerr | The Galactic Center & Sagittarius A* |
Note: These systems are original, hand-crafted gameplay adaptations tailored specifically for KSP mechanics rather than 1:1 scientific simulations.
The event horizon of Kerr, observed from orbit around Grav. (Scatterer + EVE Volumetrics)
 |
 |
|---|---|
| Aethera demonstrating why radiation shielding is not optional. | The twilight domain of Kormin and its frozen satellites. |
 |
 |
|---|---|
| Sunrise on Blalo beneath the Nova Kirbani binary glare. | The jagged, unforgiving surface of Xolem. |
 |
 |
|---|---|
| Polynovin and its surrounding orbital hierarchy. | Kerr: The ultimate test of orbital capture calculations. |
Access the Operations Wiki • Join Mission Control (Discord) • Watch Visual Archives (YouTube)
Managing a galactic-scale mod requires adherence to strict deployment guidelines. KSS2 utilizes a modular manual installation to safeguard your save files from the Kraken.
| DEPLOYMENT SEQUENCE | SYSTEM REQUIREMENTS |
|---|---|
|
KSP Engine Version1.12.x
Memory (RAM) 16 GB absolute minimum. 32 GB recommended for full modular and visual suites. Graphics (VRAM) 1–2 GB minimum. Volumetric cloud suites will demand considerably more graphical overhead. Package Manager Manual installation strictly required. |
Important
Why is KSS2 not on CKAN? Automated package managers are wonderful tools, but they struggle to manage the immense structural and modular complexity of an interstellar asset library. Manual installation guarantees that you avoid conflicting dependencies, broken file paths, and silent memory leaks. Read the wiki; your save files will survive.
KSS2 is built to coexist with robust visual and systemic overhaul frameworks, but certain conflicting modifications will cause catastrophic save corruption.
Consult the full Compatibility Matrix before launch →
Known Fatal Incompatibilities (Click to expand)
Do not attempt to run KSS2 alongside the following modifications:
- Principia (N-body orbital mechanics conflict with fixed multi-star coordinate systems)
- Galaxies Unbound (Legacy file conflicts)
- Better Kerbol
- Legacy Parallax configurations
Compatibility parameters shift with updates. Check the matrix before assembly or at least before filing a bug report blaming the nearest gas giant.
The surface of Kaith. Landing gear durability results may vary.
Development continues as long as there are stars left to map.
| ACTIVE ENGINEERING | CLASSIFIED CONCEPTS |
|---|---|
| Expanding planetary bodies across the Orbel and Seereon systems | An experimental, high-risk star system centered around an active pulsar |
| Refining atmospheric behaviors and surface topography | Distant exploratory anomalies situated past the outer edges of Eeloo |
| Introducing dynamic stellar-evolution visual states | Closer mechanical hooks between local Kerbol operations and deep-space missions |
| Continuous optimization, memory management, and compatibility patches | Additional specialized survival challenges for veteran commanders |
Note: Classified concepts represent ongoing research paths rather than guaranteed delivery dates. Mission parameters are always subject to revision following technical roadblocks or explosive testing accidents in the VAB.
| COMMUNITY FREQUENCY | DEVELOPMENT LOGS | PROJECT SUPPORT & BACKING |
|---|---|---|
| Discord Headquarters | YouTube Archives | Support on Patreon |
| Installation support, mission debriefs, and community discussions. | Cinematic trailers, system previews, and engineering logs. | Voluntary funding for development tools, assets, and maintenance. |
| Report Anomalies (GitHub Issues) | Operations Manual (Wiki) | Free Access Policy |
| Bug reports require player logs and clear replication steps. | Full documentation on system data, installation, and patches. | KSS2 is free. No content is ever locked behind a paywall. |
Bug reports submitted without player logs or reproduction steps will be unceremoniously jettisoned into the sun. Screenshots of your spacecraft undergoing rapid unscheduled disassembly in deep space, however, remain thoroughly welcome for crew morale.
TheSpacePotato · Spaceman · OoglakKerman · JadeOfMaar · Emu · Caden · Chaotic Protocol · Ciara Rayne Cloud · Bogue · The invaluable community testers and exploratory pioneers.
Special commendation to TheSpacePotato: Co-pilot since 2016.
Licensing, Transparency, & Regulations (Click to expand)
KSS2 uses a granular, component-level multi-licensing structure. Under international copyright law and Creative Commons Official Licensor Guidelines, a creator who holds exclusive copyright to all project materials maintains the legal right to apply distinct terms to different components of a work. As explicitly outlined in Creative Commons documentation: "Any given work has multiple elements; e.g., text, images, music. Make sure to clearly mark or indicate in a notice which of those are covered by the license."
Starting with the next update moving forward, KSS2 officially features and enforces this structured split across two strict legal tiers:
- 🎨 PLANET & CLOUD TEXTURES (ALL RIGHTS RESERVED): All custom planet color maps, heightmaps, normal maps, and volumetric cloud textures created by my hand (StarCrusher96) are protected under StarCrusher96 - All Rights Reserved. Ripping, extracting, converting, or reusing these specific visual assets for any other mod, compilation pack, or external project is strictly prohibited.
- ⚙️ CORE FILES & CONFIGS (CC BY-NC-ND 4.0): All remaining system frameworks, layout structures, and configuration files are distributed under CC BY-NC-ND 4.0.
To eliminate ambiguity, the following operational boundaries are absolute:
- ✅ PERMITTED: Non-commercial sharing, media coverage, and community showcasing of the official package, strictly conditioned on explicit, proper attribution to the original author.
- ❌ STRICTLY PROHIBITED: Redistributing modified, "tweaked," "optimized," or unofficial alternative versions of core files, system files, or planetary packs.
- ❌ STRICTLY PROHIBITED: Creating unauthorized derivative works of any kind. A derivative is explicitly defined as anything based on, adapted from, or created from KSS2's pre-existing source code, planetary design, layout, mechanics, ideas, or asset library (including unauthorized or custom system-altering configs), whether published publicly.
- ❌ STRICTLY PROHIBITED: Extracting, ripping, converting, or reusing KSS2 code and system assets (including config nodes, system architectures, and models) for separate mods, third-party compilation packs, or external game projects, regardless of whether credit is given or financial profit is involved.
The official, verified repository source for KSS2 is exclusively: github.com/StarCrusher96/Kerbal-Star-Systems-2
Independent community side-projects, compatibility patches, or alternative setups (such as custom homeworld configurations) fall completely outside official KSS2 Command support.
- If you run modified configs or unofficial system alterations, you are on your own. Do not submit bug reports to our GitHub or Discord. Address all troubleshooting directly to the third-party authors.
- Spotted a violation? If you encounter unauthorized mirrors, stolen assets, or illicit derivative packages hosted elsewhere, please inform the Devs immediately via our official Discord server.
KSS2 honors original development work, clean licensing compliance, transparent attribution, and mutual respect within the modding community. Read the Transparency and Asset Policy →
FROM A SINGLE WOBBLY ROCKET TO AN ENTIRE GALAXY.
Leave Kerbol behind. We'll see you in the black.