For far too long man has been under the misconception that our planet Earth has an infinite supply of resources and space to service our growing population. With our population soon approaching 6 billion, the urgency of conserving natural resources is becoming of great importance.
Some people believe space exploration may hold the answers to our population explosion. What are the chances of another planet existing in our galaxy so similar to Earth that we could hope to colonize such a planet? If the Sun is considered to be an average star, and planets seem to form around stars naturally, then planets at our temperature range should turn out to look similar to Earth. Life on these planets should be based on carbon, oxygen, and water. Given enough time and natural forces, the same evolution that occurred on Earth could occur on similar planets.
The question in not: Are there worlds out there that could sustain human life? The question that needs to be answered is: Is it possible to travel to these distant worlds?
A rocket would have to reach a burnout speed of nearly 58,000 kilometers per hour to escape from the Sun's gravitational influence. The best we have been able to achieve to date is somewhere around 40,000 kilometers per hour, for the rockets that have gone to that moon and the planets. Even if a rocket could keep going at its top speed of 58,000 kilometers per hour-which it won't, once the rocket engines shut down-it would take 80,000 years to reach Alpha Centauri, the next nearest star. This is the closest star to our solar system, 4.3 light years away. Even if we could travel at the speed of light-which is 300,000 kilometers per second-it would take 4.3 years to get there. (Nothing in the Universe has been observed to travel faster than the speed of light.)
Let's just assume for a moment that we could build a ship that could travel at the speed of light, the ship would still have to carry its propellant fuel with it. The rocket would spend a considerable amount of its energy just lifting its own fuel mass. As long as you have to carry all the rocket's propellant along with you, any increase in speed must be paid for by more propellant mass. This is a major obstacle to traveling at the speed of light. Even if you could overcome this obstacle, you would have to leave the Earth, knowing that the ship would return to a world that is several thousand years older than the one you left. In reality you would be taking a one way trip.
