The concept is mind boggling and very humbling due to the time scales involved. We can talk about an event that won't happen (we won't observe) till a thousand years from now although it already happened 6000 years ago by inferring from physical laws. Most of the universe around us is in snapshots from long ago.
It was announced in 2007 that the Pillars of Creation were destroyed by a supernova's shockwave about 6,000 years ago.[8] Because of the limited speed of light, observers on Earth currently see the shockwave approaching the pillars, and will not see the destruction occur for about another 1,000 years
It was announced in 2007 that the Pillars of Creation were destroyed by a supernova's shockwave about 6,000 years ago.[8] Because of the limited speed of light, observers on Earth currently see the shockwave approaching the pillars, and will not see the destruction occur for about another 1,000 years
http://en.wikipedia.org/wiki/Pillars_of_Creation