Fans of Star Trek easily imagine that, given the technology, travel between star systems would be no more difficult than hopping a trans-Atlantic flight from New York City to Paris. The reality is, unfortunately, quite different.

The greatest challenge lies in sheer distance. Few people realize the scale of our own Solar System, let alone the universe.

To get an idea of the true scale of our Solar System, imagine our sun as being a ball 11 centimeters in diameter. On this scale, our Earth would be a marble 1 millimeter in diameter, sitting 11.7  meters (38 feet) away. At this distance, light from the sun, traveling at 300,000 kilometers per second, requires over eight minutes to reach us. Pluto would be a mere .2 millimeters in diameter, and would lie 463 meters from the "sun"  - nearly half a kilometer away! Sunlight itself takes five-and-a-half hours to reach Pluto's surface.

On this scale, the nearest star - Promixa Centauri would be 7435 kilometers (4,620) miles away - roughly the distance from the east coast of North America to Continental Europe. The time required for light to travel this distance is over four-and-a-half years.

Despite these distances, scientists are speculating their are ways around them. Read on...