Indeed, some parameters must be taken in account :
We may see specist movements appearing like in science fiction, based on physical criteria (see racism within humankind)Â ;
We may see religious movements appearing to fulfill a prophecy or a specific vision, like :
Adoration, if they are beautiful (physically or through other means, like advancement) ;
Destruction, if they are not, kind of like in the picture (and as this view would become mainstream this could lead to "holly space crusades" which are extremely damaging and unfortunate) ;
Finally, being at the proximity of one of them could trigger gut or anger reactions — emotional relieving of hormonal particles in the surrounding, both for you or them, that could trigger specific (biological) responses ;
Lastly, the biological soup compatibility, your bacteria and virus coming from Earth may not be compatible with other ones coming from above — for what we know of carbonated lifeforms ;
All this criteria perfectly expose the required need for preparedness before meeting other intelligent species — or siblings — both in term of psychological walls to put down — like for physical only criteria — but also biophysical ones for behaviors, physical movements, hormonal reactions, etc.
To maximize the chance of a contact taking place as well as possible, first Humans astronauts may pass through hard training both of the body and the mind, before your kid could safely play chess with a giant space-ant in the future.
