Often stands for "The Onion Router," a method of anonymous communication on the internet. However, without more context, it's hard to say if this is relevant.
For astronomers, night crawling could metaphorically describe the act of staying up late to observe celestial bodies. This often involves heading to dark-sky preserves or locations with minimal light pollution to get a clearer view of the stars. fu10 night crawling 17 18 19 tor top