The original Star Trek, which aired from 1966-1969, was and still is one of my favorite television shows of all time. Notwithstanding some corny special-effects and overacting on the part of the cast at times, this program provided our society with a positive vision of the future. A massive Starship capable of warping the time-fabric of space carried four hundred passengers to the unexplored reaches of our universe. Along the way, many diverse worlds were discovered. Some were far advanced while others were quite primitive. Controversial issues were depicted to be widespread everywhere and not just isolated to our tiny speck of life known as humankind on our equally tiny planet called Earth. This fictitious setting took place in the 23rd century; give or take some 200 years from now.
At the time this television series was produced, The United States was in the midst of a ambitious space race with the Soviet Union. From the time Sputnik 1 was launched into orbit in 1957, it seemed as though the fantastic visions of imaginative science fiction writers would soon become reality. In 1961, President John F. Kennedy set a goal for our nation to reach the moon before the decade was ended. Beginning with the Mercury and Gemini programs, we eventually surpassed the U.S.S. R. and accomplished this task with Apollo 11 in 1969. The Apollo moon missions continued for a few more years and then abruptly came to an end. Budget cuts suddenly placed limitations on manned space flight. A mission to Mars had once been predicted to take place by 1973, but still remains years away as of this writing in late 2008. While many unmanned spacecraft have been launched and sent to several locations, manned space flight has been restricted to orbital Shuttle flights. On the upside, we have developed the Hubble Telescope, and while not perfect, this colossal instrument has unlocked many secrets to the universe. As we had predicted for perhaps centuries, we now know that there are other planets out there orbiting distant stars. Spectacular images of other worlds taken from unmanned spacecraft have enabled us to learn a great deal about our solar system.
Yet this is not enough. As an intelligent species; one that continuously seeks to expand our knowledge, the vastness of space is a wide-open frontier that beckons. It is highly unlikely that we are alone and it becomes prudent and in fact compulsory to satisfy our curiosity. Whether we overtly acknowledge it or not, we long to meet others who may be out there. And this unfortunately presents a problem. Albeit the necessary funding to whet our appetites, the sheer distances to other solar systems are enormous. The very closest star beyond our sun is over four light-years away. Even those a few hundred light-years distant are considered "neighbors."
How would it be possible to travel such distances? Well, there's a little thing called time dilation. The closer a ship travels to the speed of light, the slower its occupants will age. The traveler would be at an advantage, for he or she in theory could arrive at our closest "neighbors" within a lifetime. The problem is that when they returned to earth, centuries would have passed. Everyone and everything he or she knew would be long gone. Imagine Christopher Columbus setting sail across the Atlantic in 1492 and arriving in the Caribbean a few months later. His crew spends some time there and decides to return to Europe. From their point of view, a few more months would go by, but if they had been traveling through space at 9999/10,000 of the speed of light instead, it would now be past the year 2000! In order for humans to explore even our nearest solar systems, they would have to accept the fact that everything they ever knew would be left behind; and permanently.
If this weren't enough of a problem, then consider this: the energy required to propel just one modest 10-ton spaceship to a velocity approaching that of light would currently supply our entire global needs for a period of about 200 years! It would probably also involve the complete annihilation of matter, and we really don't know how to do that yet. The risk of destroying everything around us is something few would agree to taking. We will either have to find a way to dispel Albert Einstein's proclamation that nothing can go faster than light, or stumble upon shortcuts that would enable us to get to these destinations one hell of a lot faster. Unlike the vision of Gene Roddenberry and Star Trek, I don't think this will happen in a mere 200 years; if ever.
Realistically, what we can hope for in the next couple of centuries is perhaps a permanent Space Station (or several) placed in Earth orbit. Maybe we'll have artificial-environment colonies on the moon, Mars and/or a few satellites of the gas giants further out. I would venture to guess that the exploration and colonization of our own Solar System will take far longer than 200 years.
As for the rest of the universe, we will learn more by building larger telescopes. We may even be able to communicate with a few of the nearest inhabitants; assuming they're out there, but we'll have to wait a long time between replies. As for visiting them, it is of this author's opinion that this will prove to be impossible.
It's a shame, really. But the universe is simply too big. And it's still expanding.