Why Don't The Aliens Just Land?
Sorry, but I truly think DUH when someone asks the question, why don't they just land. Imagine yourself as a being who may be out exploring foreign planets, and happen upon one that holds intelligent life which have systems of defense, weapons, and many unknowns. Would you really land in the middle of them in open view and expose yourself to the possible dangers? Seriously, our earth scientists if they had the capability would probably set up shop with studies -- doing everything from watching the beings to hands on experimenting (especially if we were more advanced and the life was foreign to their knowledge). The alleged actions of ETs that people claim, really makes sense considering what any exploring scientist might do if a foreign planet was found. Even if you were more advanced, or older in a sense (your planet may have held life for longer than the foreign planet), doesn't necessarily mean that dangers wouldn't exist for you or that you could always outsmart the foreign life on the planet. Even if scientists spent thousands of years on the foreign planet studying it and have great knowledge on how it works, doesn't necessarily mean that the dangers of exposing yourself wouldn't exist. It would be idiotic to land in open view where their massive weapons and defensive systems would swarm you, especially if you wanted peace, freedom, and understanding. If you weren't capable of engaging in the same means of communication because of the foreignness of the species, you definitely could cause misunderstanding, confusion, fear, distrust, panic etc. The reasons why aliens don't land in the open could be many, depending on their motives and agendas for being here, but it should be quite simple to see the many possibilities, just put yourself in the shoes of what exploring scientists might do. IMO, our history is rich with written evidence that we've been visited for thousands of years and have had much misunderstanding and confusion that has resulted.