Asteroid Mining

What You Need

Asteroid mining requires the Mining Ship (Shipyard level 3; research: SHIP_MINING_SHIP, prerequisite: SHIP_BULK_HAULER). No other ship type can initiate a mining dock. See Ships and Shipyard for details.

To reach an asteroid, dispatch a fleet from the Fleets and Missions Send-Fleet screen, selecting an asteroid as the target. The fleet travels like any other fleet; travel time depends on distance and ship speed.

Mining Rate

Each Mining Ship in your docked fleet extracts resources from the asteroid continuously. The rate is split by the asteroid's composition — what fraction of its pool is metal, carbon, and hydrogen. A metal-heavy asteroid yields mostly metal; a more balanced one spreads extraction across all three resources.

Asteroid Composition

Asteroid composition is determined at spawn and is fixed for the life of that asteroid. Every asteroid is metal-dominant — metal always makes up the largest share. Carbon is capped at a lower maximum, and hydrogen is always scarce (under a tenth of the total). This keeps every asteroid metal-and-carbon-led, with hydrogen a small bonus. A fallback composition applies when random generation cannot satisfy the constraints.

Dock Loot Cap

Your dock cannot hold unlimited cargo. The loot cap is a fraction of the asteroid's current remaining pool. Once your dock buffer reaches this cap, extraction pauses — your ships remain at the asteroid but pull nothing. You must transport the buffered resources away before mining resumes.

Use TRANSPORT missions with returnAfterDrop = true to create a continuous supply chain: a hauler fleet shuttles between your dock and your nearest planet, freeing up cap space so extraction keeps running.

Hydrogen Upkeep

Keeping Mining Ships docked costs hydrogen — your ships need fuel to maintain station orbit. The upkeep model is progressive: the first ships in a small fleet are essentially free to maintain, but each ship beyond a threshold costs more hydrogen, growing as a power law.

Free band. A small initial fleet burns no meaningful hydrogen upkeep. Beyond that threshold, upkeep per ship grows quickly.

What this means in practice: small fleets mine for essentially free. Larger fleets pay increasing upkeep. At some point, adding another Mining Ship costs more hydrogen than it earns from mining — there is an economic optimum fleet size per asteroid.

Running out of hydrogen. If your dock runs dry on hydrogen, the dock enters a fuel-starved state — ships stay parked but mine nothing. Resupply hydrogen via TRANSPORT to resume extraction.

The Dock Buffer and Transport

Extracted resources accumulate in your dock buffer — a cargo pool attached to your docked fleet. To move resources out, send a TRANSPORT mission to the asteroid (targeting it by ID from the fleet dispatch screen). The transporting fleet picks up resources from your dock buffer and carries them to your chosen destination.

Practical workflow:

1. Dock a fleet of Mining Ships at the asteroid
2. Monitor the dock panel for buffer level and hydrogen runway
3. Dispatch Haulers or Bulk Haulers on TRANSPORT missions to collect from the dock
4. Use returnAfterDrop = true to keep the haulers running autonomously

Asteroid Sizes

Asteroids come in three size classes — Small, Medium, and Large — each with different total resource pool ranges. Larger asteroids carry bigger resource pools, so at a given fleet size they take longer to deplete; smaller asteroids drain faster. An asteroid's orbit (its distance from the galactic center) is independent of its size.

Pool size is also scaled by the server's economy speed setting, keeping wall-clock depletion time consistent regardless of how fast the server runs.

Asteroid Lifecycle

An asteroid passes through three phases. First it is Active — the pool is being drawn down and any docked fleet can extract from it. Once the pool hits zero the asteroid enters a Depleted state: the rock lingers on the map for a fixed window, docked fleets remain parked, but nothing can be mined. After that linger window expires, the slot enters a randomized cooldown before a fresh asteroid spawns in its place — the Gone / Respawn phase.

The server maintains a minimum floor of active asteroids — when the count drops below this floor, new asteroids are spawned to refill. There are always asteroids to mine; the question is where and how rich they are.

Combat at Asteroids

Your docked fleet can be attacked. Enemy players can send an ATTACK mission to an asteroid coordinate. The docked fleet fights as a defender. If your fleet is destroyed, your dock buffer (up to the loot cap fraction) is captured by the attacker as raid loot.

Key rules:

• A destroyed mining fleet loses its dock — you must send a new fleet to resume
• The asteroid itself is not destroyed by combat; other docked fleets continue unaffected
• Alliance STATION missions extend to asteroids — you can park defenders alongside your mining fleet

See Combat for how combat resolution works.