can works be orphaned?

I found the idea of orphaned works interesting and my first thought was of really old works, like photographs, diaries, etc. Some of these types of orphan works could really help in research, but without a clear owner of the works should they be public domain? If a library was given a huge collection of these types of works - what could they do with them legally? Would they be allowed to add them to the library collection and allow anyone to come in and look at them? This is just one scenario I would like to explore in the next few weeks.

Abandonware is a type of orphaned work that is specifically computer software. One of my first reactions to this topic is that if a work is orphaned, should a copyright be valid? If there is no clear owner and a thorough search has been done to try to find the owner, what would be the next step? From my readings so far, it seems most people leave the orpahned work alone and move on.

I am excited to learn more about orphaned works and abandonware.