in an article on
universe today scientist have created a tiny hopping robot for exploring mars. the idea is to send a thousand (probably many more) to mars an unleash them so they can explore the planet. the hopping bots are "expendable" and therefore would be just left to pollute (in my opinoin) the surface of this near pristine uninhabitied planet.
are we going to leave rubbish there to make us feel more at home when/if we inhabit it???
http://www.universetoday.com/am/uploads/microbots-1.jpg