I am wondering if there are any lines of longitude that do not cross any land at all (except, of course, Antarctica). We all know that the 180th comes sort of close, but it crosses a chunk of Mainland Asia in Siberia, as well as a couple of Fijian islands.
I’m not necessarily referring to longitudinal lines that are whole degrees (like the aforementioned 180), I don’t think any of them fit the bill anyways, but maybe something like 171d 42m 38s W (randomly picked, not tested) - in fact, I think the 170s W are our best shot.