Factories in SpaceAlpha are used predominantly for spaceship production. Ships can be used for a wide variety of things, from transporting resources and ground troops to other planets, to attacking and defending planets/other players. Each ship excels at different tasks and have their own limitations.
Factory production speed is influenced by a few factors, mainly the number of engineers that aren't being used by facilities and the level of the factory, but there are several others as well.
Factories can also produce Widow Mines and SSBs (Standardized Space Battery), neither of which are technically considered ships/units.
Probes are extremely fast and carry no resources or units. They are used exclusively to scout various intel on another user's planet. Their effectiveness is boosted by the amount of existing spies in the empire. They also have a niche use, in being sent to detonate Widow Mines as a fast and cost effective method.
Resource
Scout for how much gold/iron/trit/coal/steel the player has.
Tips: This is generally the first thing you would scout for if you're looking for an inactive to raid. There's no point in scouting for their defense first if you end up finding they have very few resources and they aren't worth raiding.
Defense Force
Possible results: how many defense units of each type there along with their total defense.
Tips: You can usually figure out if their defense dome is on if their total defense units don't properly add up to their total defense.
Attack Force
Possible results: how many of each attack unit they have along with total attack strength.
Special Forces
Possible results: how many assassins, spies, and security officers they have.
Civilians
Scout for farmers, industrial workers, commercial workers, mine workers, doctors, engineers, scientists, teachers, professors, foresters, and factory workers.
Tip: If you want to find all of this information, you'll need to send multiple fleets as one espionage mission cannot relay all these unit types in one report.
Factory Forces
This will tell you how many ships and what type they have at their planet.
Tip: This won't reveal how many ships are mining or transporting units/resources, as they are technically not in orbit around the planet target.
Defensive Facilities
Possible results: activation status of Gap Generator, Planetary Defense Dome, and Widow Mine Charger.
Power Facilities
Possible results: Coal, Tritium, Solar, and Wind power facility status, as well as the tritium accumulator.
Civilian Facilities and Mines
Possible results: Gold and Iron mines, tick generator, wood cutters, carbon scrubbers, and food factories.
Colony ships have one purpose and one purpose only, to colonize another planet. They are consumed upon use and move at a very slow speed. If colonizing another planet, it's best to send only one and use other ships to move the rest of your units/resources after the desired planet is colonized.
When using one, it HIGHLY recommended to load it with a decent amount of tritium and burn it at 100% for the majority of the trip, this will provide a roughly 80% reduction of flight time.
Miners are the only ships that you can use to mine either iron planets or tritium gas giants. Thankfully they're the third fastest ship following the Probe and the Invader ships. However they are costly in terms of gold/credits, quite slow to produce, very weak for the cost, and should therefore not be used in combat unless left with no other options.
Widow mines orbit the planet and damage ANY incoming fleets. Whether it be friend or foe. Build widow mines if you are going to experience an incoming attack that your current forces will not be able to defend. It's considered a final defense.
It's important to note that not only do widow mines attack friendly units, whether it be a reinforcement or a returning mining fleet. When you want to get rid of them you can only defuse 10% of the existing widow mines at a time.
They are cheap to make with a low production power requirement and when coupled with a high level widow mine generator, can be devastating to an incoming attack.
The percentage of chance to hit increases with how many widow mines are in orbit and the level of your gap generator.
Dealing with widow mines around a target planet?
The most efficient solution is to send single unit fleets of probes at the planet over and over to detonate the mines. This is obviously going to be a slow operation if you don't have many fleet slots available, if you are in a hurry, consider using a /game-resources/Cards-Heroes.
These units are either meant specifically for combat actions, or are well suited to them.
When selecting the Attack category on the Send Fleet panel, you are given 4 different attack categories.
Steal Credits
This will simply take credits from their planetary credit pool. It will not touch anything in the bank.
Raid Resources
This will simply take from their planetary resource tab, any combination of iron, gold, tritium, steel, or coal.
Capture Untrained
This will take from their untrained pool and turn them into slaves.
Free Slaves
This will take from their slaves, both untrained slaves and mining slaves, and turn them into untrained. However, often times this is not worth doing, as you would be reducing the target planets generation of credits/iron/gold, making them a worse farming target long term.
Producing invader ships generates the most strength per production power(minute) at the cost of using the most resource value in credits per minute. This calculation takes into consideration the troop space being filled with attack soldiers and uses generalized market values from 6-21-24.
They have an additional benefit, in that they are the fastest ship at 14 base speed, making them ideal for trips in between star systems.
Space fighters are the cheapest to produce in terms of credits per minute, but also the slowest producers of strength. Fighters make 27.6% the amount of strength(of invaders) at 22.02% the cost, making them a great choice if you are trying to maximize cost efficiency.
They are 71.43% the speed of Invaders as well.
Carriers have multiple purposes making pure numerical calculations less reflective of value, but they are 43.5% the cost per minute of invaders and 65.5% the strength per minute. When you consider their flexibility in usage, that makes them a great safe choice for factory production. They are often a great addition to mining fleets to extend mining times with their enormous carrying capacity, and very good for any operation that involves delivering resources between planets or delivering ground units such as assassins.
Their largest downside by far is their glacial speed of 6, 43% the speed of invaders.