Star travel, just the thought of it is enough to excite this old heart of mine. Presently it is out of the question unless we are willing to wait beyond our lifetimes for results to be returned. Right now we are just getting into the new Ion engines. They accelerate xenon gas by ionizing it and this is turn pushes the ship. It is said that the new DS1 engine can reach about 30 km/second. To better understand what we are talking about, light travels at about 186,000 miles per second. The engine will get the space craft up to 18 miles per second. It sound very fast but when you compare it to the speed of light it is still pretty slow. It is less than 1/10000 the speed of light so that a trip that takes light one year is going to take over 10,000 years. These figures are not precise since I just rounded them off, but I think that you get the idea. We need much faster engines.

If we use engines like the DS1 for travel around the solar system it still presents a problem. The engine takes quite a while to reach top speed. I am talking months, so the further away the planet, the more efficient the DS1 is for propulsion. It wouldn't be any help in going to a place like the moon because it wouldn't have a chance to build up speed. At top speed the DS1 is about 10 times faster than a rocket. This is not really a new technology, NASA has had it since around 1960, but no one wanted to risk an expensive probe on it then. Now let me surprise you, DS1 stands for Deep Space 1. It was launched in October of 1998. It was able to accelerate at a rate of 10,000 mph until it's fuel was exhausted which would last 26 months at full burn. Guess what, the engine used on DS1 has already been improved and there are things that can be done to increase fuel capacity and build a bigger array to give more voltage.

One of the things that I find ironic, is the fact that many scientists are pushing solar sails as the propulsion unit of choice. I can't help it, it just reminds me of man's early efforts in sailing the seas of Earth. By the time of the ancient Greeks, a primitive steam device had been discovered but no one thought to harness it's power. If they had, we could have been 2,000 years further ahead in technology than we are now, and we no doubt would have been to the stars already. So now they want to use this primitive sailing technology again. Of course it is the solar wind that they are trying to harness this time. Some claim that a solar sail will get you to Jupiter in about two years. This might be all well and good, but it is still to slow and by the time you got to Jupiter you would be so irradiated that your life would be finished, that is if you could make it there. It is true however that the solar wind travels at an average speed of 800,000 mph or 400 km/sec with is even faster than the ion engine in DS1 by a factor of 13. I wonder how difficult it would be to travel against the solar wind?

Ion Engine

Here is a thought for you, if the sun can send out particles traveling at 800,000 mph, why can't we discover the method being used and build an engine to do this? Scientists have made a discovery in this area and have found out that heavier oxygen ions travel faster than lighter hydrogen ions. They have also found that magnetic waves play a big part in the speed of the solar wind. It seems that the wind travels about 2 times faster than expected and this is because the particles are riding on the waves of the sun's magnetic field. But a new ion engine has been designed by the European Space Agency. It is said to be 10 times as fuel efficient. I am not sure if it can bring a craft up to ten times faster or not, but it is certainly much faster that the engine used in DS1. The test model of the new ion engine was very small but still produced 4 times the speed of existing ion engines and scientists state that it will be scaled up giving it more power and speed.

I certainly am not a rocket scientist, but I know that for every action there is a reaction, because Einstein told us so. This means that even light from a flashlight would push the flashlight forward in space. Are there other methods of travel that we could use to power our space ships besides rockets and ion engines and even solar sails? Yes, a new theoretical engine is being investigated by the U.S. government. As I said, it is theoretical, but if it comes about, travel to Mars would take only 3 hours and a light year would take a little over a week to travel. Look out Scottie here comes warp drive! This has been reported in New Scientist magazine. The principles behind it are producing a gravitational field that provides thrust and also allows the vehicle to slip into a different dimension where light travels at a faster speed. As you might guess, this is all quite controversial right now, but it is being taken seriously. If this works. it would be the first truly interstellar engine and make planetary travel as convenient as train or plane travel. As far as when the engine could be built, one scientist thinks that a test device will come along within the next 5 years.

Lunar Reconnaissance Orbiter
Quicktime Movie 4.76 Megs

NASA is doing a study on creating an antimatter engine for a spaceship. The new design will substitute positrons instead of the antiprotons that have been attempted in previous exercises. Antimatter presents certain problems. While it is the most powerful fuel known, it takes years to produce a microscopic amount that would be hard to find on the head of a pin. It can also cause engine parts to become radioactive. Unwanted explosions and dangerous gamma rays also can cause problems. The gamma ray problem can be softened somewhat when protons are used because they produce gamma rays about 400 times less. In an antimatter engine of this type a positron reactor is not radioactive when it's fuel is used up like a nuclear reactor which can stay radioactive for a million years. If the positron reactor was to explode on launch the danger area would only be about a half of a mile and would only last for a split second and there would be no radioactive material to rain down on anyone. Research shows that it might be possible to reach Mars in such a ship in as little as 45 days.

We need speed to travel among the stars and planets and it seems that new technologies are only a few years away. It will be glorious to see us in a hundred years, if we don't destroy ourselves first. By then we should be routinely traveling among the stars and maybe even meeting other races. I just hope that we are not engaged in any interplanetary wars by then.