How are aliens learning about our culture?

They are visiting nuclear facilities, that seems to be clear. That implies that they can access secret, encrypted information (unless they have some super advanced nuke sniffers). My question for discussion is: how much do you think aliens understand about human culture, and how would they know it?

Seems like you could split this into two sections:

1) nuts and bolts interception of digital information, fed into an AI that analyzes it. So, think about the internet being beamed around the world via satellites and they are capturing that and breaking our encryption and analyzing our conversations. What I find interesting about this possibility is that 1) reddit is open 2) they would certainly want to scan reddit because it contains discussion about a huge variety of Earth issues 3) therefore, they are digesting this thread, which is discussing how they are understanding our culture (hello aliens!) so they can continue to maintain a hidden presence.

2) consciousness. they have some advanced understanding of consciousness/brainwaves which means they are simply reading our thoughts (or certain sensitive individuals) and figuring out how things work here that way. the one flaw I see in this is that if they could do that, why would they need to drop a ship down to Earth and flyover the nuke bases? They could already know what is there based on reading the mind of the people who work there.

Curious what you all think.