How to organize a social visit to a department?

Question

I'm going to a foreign city to meet a friend, and while I'm there I figure I might as well visit the local university and talk to the researchers in my field (astronomy) to find out more about what they're working on.

Who do I contact about this kind of visit? I don't know anyone there personally, and there's nobody in particular that I'm interested in meeting. I haven't looked through their personal pages (much less publications) either. Should I? It looks like a fairly large department, with ~20 researchers at postdoc level and above + some 50 PhD students; checking out every one of them will take time.

Answer 1

In the US it would be appropriate and possibly necessary to contact the head of the department in which astronomy resides. For foreign travel, do something similar, depending on the organization of the university. You need permission to avoid security issues. Strangers wandering around are an issue.

In pandemic times there may be special restrictions. Many large faculty have some sort of "coffee lounge" where they gather informally. It is a good place to chat with people, including graduate students in at least some places. The department head might even be willing to introduce you to a few people.

Offer to give a talk on some subject that you know well and that might be of interest to a few faculty and students. If this is agreeable, the "department" will likely make an announcement, indicating you will be present.

Indicate that you are just using the opportunity of being in the neighborhood to establish informal contacts.

Answer 2

Maybe you can join a colloquium or some other (semi-)public event by that department. Maybe you can give a talk and listen to a talk.

If that is not possible, I would think about a more concrete goal of those meetings. Imagine you get a meeting with some faculty member, you sit in her/his office, and (s)he starts with "Welcome. What do you want to talk about?" and an awkward silence ensues.