Viewing & Recording past "Events" in time..?

[Guest WetWire]

When most people talk about the possibility of "Time Travel", I would think that we all, for the most part, expect to interact in some way with the past or the future that we "Travel" to, in order to warrant and validate such a statement. But on the other hand, if we were to only hope to "observe" the past from a point of safety and not acctually try to interact with the past or future event, surely we can, and do this all the time in everyday life..?

As I understand it, all the light that enters our retinas has taken a certain amount of "time" to reach us and has traveled a great distance, so taking this simple concept to a greater scale, all the humanly visible light that has ever come from our humble little planet is still traveling outwards into space, and will do so until it effectively "hits" something, and is reflected back towards the observer.

So would one be safe to assume, that it would be possible for an observer many lightyears away from Earth, who's technology is advanced enough to resolve very faint light from very large distances into usable viewable imagery.? Or to put it simply, a huge telescope on another planet that can resolve right down to very fine scales, and observe directly, the acctual events on Earth as they happen from their point of view.? For example, I have had a fascination for many years with the sinking event of the "Titanic", and have often wondered what it was really like for the poor souls who were witnesses to the "event". Given that it was in the Middle of a huge ocean on a crystal clear night, and that the ship remained lit for most of the sinking, I would easily entertain the idea of an observer being able to view and witness this event and even record it.

Or suppose one day in the distant future, humans do learn to travel great distances away from Earth, couldnt they simply turn around and record the past if they have overtaken it.? The night sky we all observe is basicly a picture from the past, so if technology advances allows for insanely fine resolution of light, the past is recordable from anywhere at anytime I would say..! Does anybody have any thoughts on this as I would like to hear them, thanks..

[Pangloss]

It's a reasonable conjecture. One thing to bear in mind is that when photons are your transport medium, they're not very reliable. They get stopped by pretty much anything that happens to be in the way. So your distant observer would have very little to work with, even with sufficient magnification equipment. For example, an observer 60 light years away might have some success viewing the events of the Battle of the Bulge (for those periods of the battle in which the Earth was pointed in his or her direction), or your Titanic example, but very little luck trying to determine any event that took place indoors.

 

It might be interesting to do some rough calculations to show what size a telescope at 50 light years' distance would have to be in order to resolve something 5-6 feet in size using only present technology.

[1veedo]

You'd also have to expose it for a really long time. As you can tell, something that small would be all smuged up...it'd take computer enhanced imaging to take individual frames out of it.