So, I guess you heard the big news—there is flowing water on Mars.  Not exactly the Guadalupe River but NASA scientists are really excited about it.  It seems to flow seasonally, with a high concentration of salts.  So, why should they get so excited about salty water?  Well, nitrogen is a gas and it’s light but water is too heavy to carry off of this planet in the quantities we would need.  They already have carbon identified and if they have carbon and water, well, what could they do? The scientists say they can put up a greenhouse and grow plants!  Because if they could grow plants, they could feed animals and people and if they could do that—well, make your reservations now and avoid the rush!  On our planet, virtually all life depends upon the abilities of plants to take carbon and water and make sugar.  And apparently we will have to have those capabilities to boldly go where. . .