Tomorrow's spacecraft will be built using advanced materials with mind-boggling properties.
"What I'm really looking for," you say to the salesman, "is a car that goes at least 10,000 miles between fill-ups, repairs itself automatically, cruises at 500 mph, and weighs only a few hundred pounds."
As he stands there wide-eyed, you add, "Oh yeah, and I can only spend about a quarter of what these other cars cost."
A request like this is sure to get you laughed off the new-car lot. But in many ways, this dream car is a metaphor for the space vehicles we'll need to expand our exploration of the solar system in the decades to come. These new spacecraft will need to be faster, lighter, cheaper, more reliable, more durable, and more versatile, all at the same time.Impossible? Before you answer, consider how a rancher from 200 years ago might have reacted if a man had asked to buy a horse that could run 100 mph for hours on end, carry his entire family and all their luggage, and sing his favourite songs to him all the while! Today we call them minivans.