Monday, August 22, 2011

Alien Visitors: Our Friends

 
Possibly, but probably not
 
Give this some thought: apart from curiousity, there's really only one reason to visit this rock so close to a star: inhabitability.
 
Minerals, water, even gases can more easily be culled from the moons of Jupiter and Saturn, which have lower gravity wells and no population to battle... as far as we can tell. Metals can be grabbed out of asteroids practically for free by robotic miners.
 
But only the earth is in the sweet spot of being neither too close or too far from the star. A hostile visit would almost certainly entail an invasion, with most likely the elimination of the human species (the only one capable of defending the planet from space invaders before they got here.)
 
That said, the chances of an alien civilization reaching across billions of miles to take over our planet would be on the order of hitting the lottery twice in one week.
 
Without buying a ticket either time.