If you could peer through time

Suppose it wasn't possible to travel through time, but you could instead pick a point in spacetime to observe and even record. Full sensory input as if you were there, but no chance to interact or affect. Where and when would you go?

This question got chatted idly about last night at Trivia (we won, by the way) and it soon became obvious the answers fitted neatly into two categories. First, we have the Tourism options: watch the signing of the Declaration of Independence, see an early Jimi Hendrix concert, witness the Battle of Thermopylae, get a look at the primordial form of the solar system.

Then there's the Mysteries, all those nagging things that we'll never know the true answer about. To make things interesting let's say you have to be able to specify a precise time and place; this means you can't find out whether the Beale cipher or Money Pit on Oak Island are hoaxes. Let's also say it has to be on Earth. What mysteries do you want to solve for once and for all?

The first two it seems everyone comes up with are the Resurrection of Jesus Christ, and the grassy knoll in Dallas 1963. Close behind is Jack the Ripper. After that we fall off into ones that are easy to think of, but that really, when I stop to think about them, I can't say I care that much. Where is Jimmy Hoffa? It was important then, but how much does it matter now? Amelia Earhart? The Lindberg baby? D.B. Cooper? Maybe Roswell would be worth looking at. How about the Princess Anastasia? What did Mozart really die of?

I'm mildly curious about all these things, but I have this sense that there's much bigger questions needing answers, things that somehow I can't bring to mind. Maybe that's just because the "you have to know the time" limitation I imposed on myself rules out a lot of good ones (like "what made the dinosaurs go extinct?"), but even with that, I feel like there's good ones just lurking outside my thoughts.