As you go around the universe of The Infinite Black, you may notice some little symbols on the map with a green dot on them. These are called StarPorts.

Starports are what allow players to sell all the resources they have (e.g. Metal) You can also buy weapons, hull and storage as well as selling whatever junk you want to get rid of. The buy/sell prices of each resources are as follows:

These starports can be found in just about any area including invasion sectors, Earth, grey, black etc

It is especially useful to have Starports around when farming as you won't have to travel very far to sell your resources. You can also heal yourself at a StarPort at the rate of $1 per 1 Hull by long pressing on the StarPort outside of its menu. However it is better to use the metals that you already have since it is much cheaper than healing yourself at a StarPort or buying metals.

Organics $50 $25
Gas $100 $50
Metals $150 $75
Radioactive $200 $100
Darkmatter $250 $125

Note: Start ports dont always stay in the same place, only  the ones in garrisons and planets stay still.