What a monitor becomes in space warfare

Are there monitors in science fiction, and what would one look like?

Yes, especially in Warhammer 40,000. Bombardment and local-defence roles both supply analogues, although the panel disputes some examples.

Two monitor roles appear in the science-fiction examples: planetary bombardment and local defence. Warhammer 40,000 is offered as a setting with many such vessels. The Death Star receives a separate nomination as a bombardment monitor. A later objection says there are no monitors in Star Trek or Star Wars, exposing disagreement about whether the term describes a named class or an analogous job. The answer therefore depends on which historical meaning of monitor is being applied.