So in my explorations I've come across several planets that launch missiles at my survey ships, but when I send a scout with active/passive sensors there are no contacts. But the planet will still shoot at my scout. What is launching these missiles, and how do I deal with it? Also they will launch a 40x size 24 missile salvo that just sits on the planet until my ship leaves (could be days later). Often there will be other wrecks around these planets, so I'm not the only one they are shooting at.
I can't shoot at something that isn't a contact, right? But if I try to land troops on this planet my ships will be destroyed as soon as they approach. Are these precursor planets? They are usually colony cost 2, so I really want them.