posted on Mar, 1 2013 @ 03:32 PM
This is all just based on my own thoughts and logic.
When our galaxy burst into existence, aided by the explosion of our sun being born.
The sun would have been a blue dwarfe, a lot hotter than it is now ( presumably), as every thing started to cool as the sun cooled (however long that
took) planets formed and all that business.
This is we're I think it gets interesting, the sun was most likely too to for earth to sustain life, it could have sustained life on mars for maybe a
few billion years???
It cooled though down to a yellow sun and life could have just died out.
It was still very hot though as earth came into its ideal temp for life. Most creatures had incredibly thick skin ideal for the heat like dinosaurs
life found the only things that could live on the harsh arid plains in the hot light of a young yellow sun.
They got wiped out, and as the sun has one on it has cooled even more and allowed other species more capable of surviving the mid cooler stages of the
suns growth. I can only assume this prime stage lasts longer than the blue dwarf and red dwarf stages, ( maybe wrong).
But the sun is cooling and will continue to do so until it reaches the red dwarf stage, this could very well be the end of us and could create new
life or just kill the planet. Sometime after that it will implode and Create a black hole will consume anything nearby that survived the
Clearly all this is written in laymens terms and the deeper scientific reasons (that should just be implied) have been completely glossed over, but I
think you get the idea of how things can change throughout a galaxies lifespan.