David Portree, a reporter for the internationally syndicated radio program EARTH & SKY, e-mailed to ask a question. Recently, he said, they had a listener ask how she could break it to her son that his dreams of adventure in space are not going to happen because we can't go faster than light. What would I say to such a listener?
     The plethora of science fiction movies would have it that there's nothing worth doing in space unless we can leave our own solar system, but that's by no means true. The solar system is fascinating. There are lots of exciting places we can visit, explore, learn about and eventually colonize right here in our back yard, before we need to look out into interstellar space.
     In thirty years, if we put our minds to it, we could have colonies on Mars and the moon, we could have hotels in orbit and people visiting all the planets from Mercury to Jupiter. Mars alone is a fascinating planet, with mountains that dwarf Everest, a vast canyon the size of a continent, dried-up riverbeds that were formed by rivers that are larger than the Mississippi. It's a planet with a surface larger than the entire Earth's land area.
     If I could go anywhere in the solar system right now, I would explore the surface of Titan. This is a moon of Saturn which is as fascinating as any world, and as mysterious. It has a hazy atmosphere of nitrogen and methane, and no one has ever seen the surface. From space probes, scientists speculate that it might have oceans and continents, just like Earth-- but the oceans are of liquid ethane, and the continents could be made of polyethylene. What kind of life forms could live in such a place? We'll never know until we go there!
     My next stop would be the buried oceans of Europa. Hidden beneath miles of ice, the moon Europa could have liquid oceans and a hot core. What lives in these oceans, hidden from sunlight? What marvels might we find?
     After that, there is no end of places to go, from the mysterious ice caps of Mercury (yes, ice on Mercury!) to the million asteroids circling the sun, and eventually even to frozen Pluto and beyond, to the icy reaches of the Oort cloud and the ten trillion comets that live there.
     I don't think we are likely to run out of exploring any time soon!