It's a little bit of time travel and a whole lot of cool astronomy:

Ancient Supernova Explosion Glimpsed Anew

A supernova explosion first seen from Earth 436 years ago has come back to life for astronomers in a time-travel-like astronomical twist.

By observing light from supernova SN 1572 that was slowed on its trip to Earth by dust particles, scientists can watch the outburst now as it would have looked originally.

When the explosion first appeared in the sky in 1572, Danish astronomer Tycho Brahe named it “Stella Nova” or “New Star” because it looked like an extremely bright star that hadn’t been there before. Astronomers today call it Tycho's supernova.

So today astronomers get an up-close look at the cosmic phenomenon that Tycho Brahe observed hundreds of years ago. We're only getting a glimmer, a reflection of the original. And yet I think we're now seeing more than Tycho did...

Amazing.

A well-placed and highly reflective dust cloud bounced the image of the supernova back towards earth, giving us this latter-day shot at seeing the event. This video shows how that worked:

Of course, every time we look into the night sky, we are looking looking at either the recent past (e.g., the moon) or the very distant past (e.g., the Andromeda galaxy.) But it's one thing to see these objects just sitting there, as it were, and quite another to see something happen.

This makes me wonder...are there other past events that we might get a second shot at observing? If a well-placed dust cloud can bring back an event from nearly half a millennium ago, what other options might exist for retrieving visual information on events long since past? I think we'd all have to agree that a dust cloud is a fairly low-tech approach to viewing the past, although clearly it was aided by a high-tech telescope and imaging technology. Still, it makes you wonder.

We discussed on a recent FastForward Radio whether the technology for traveling back in time is possible, and if so whether it is reasonable to expect that it will ever exist. Perhaps going back in time is not in the cards. But seeing the past is a real possibility, as the above image demonstrates.