The most wellknown theory about UFO´s is the theory of spacecrafts. The UFO´s are believed to be spacecrafts from other planets controlled by intelligent beings. For some reason they come to Earth either on a long term mission or solemly to observe. Some even believe they´re here to advise the human race for survival.

 This theory is the best accepted because it applies to our minds. Believing that it IS possible to travel among the stars, and that there ARE beings "better" than us.

 There might be a good argument against this theory. If you believe Einstein you can´t travel faster than the speed of light. By the speed of light every matter is converted into energy. Therefore it would be impossible for a spacecraft, as we know them (made of matter), to get even close to lightspeed.

 A travel between two stars would take decades, centuries or even millenia. Also at high-speed in the vaccum of space there will be some friction. The space isn´t a complete vaccum, but few atoms will be there. A long journey for a couple of centuries would slowly wear down the hull of the ship!

 This means that visitors from another solarsystem would have to travel for very long time. Either they would have to live very long, reproduce on the way or somehow reduce their life-functions on the way. It may be possible, but if they do so, why don´t they contact us after arrival of such a long journey?

 Well, they may have their reasons. Perhaps the germs on Earth is deadly to them or maybe even the hole enviroment is.

 Perhaps they don´t even consider us intelligent. To them we might be no more than an insect is to us!

 Could it be that our lines of communication is so different that we just can´t find a way to break through this wall of silence?

 Or are they already here among us?

There are many theories on that. The next question of course will be: What do they want?

 Also on this subject there have been many theories through time! But here are only three I really like to consider:

 Perhaps they are passive observers gaining data from liveforms all over the universe. That would explain why the keep out of direct contact with us.

 Talking about abductions, they may only examin us like we examin animals.

 Or like the newer theories says: They are kloning us with their own kind to make a new breed or species for some higher purpose.

 All we can do is guess....

  Could it be, that the UFO´s really just is humans visiting us from another time, probably the future? Oh yes, it could very well be. That would explain why they do not contact us. They don´t want to interfere with the past for as far as we know.

 Also, if you compare humans to the "Small Greys" -Big heads and small limbs- human in a future unimaginative to us might very well have developed this vay. The brains has grown bigger, and as for the limbs they don´t need them much because of their fantastic machines doing everything they´re commanded.

 They might conduct experiments with us for some unknown reasons possibly trying to solve a problem in the future.

 Then again - is it really possible to travel in time? It depends on how you look at it. Timetravel forward in time IS possible. Speed up a spacecraft and the time will slow down. You could also slow down your lifefunctions (like cryocoffins in movies) to return them to normal in the desired future.

 But travel back in time might cause another problem as far as we know. Is it possible travelling to a time that have already passed? That is actually a major question asked among leading scientists all over the world today.

 Finally you could ask yourself - What if there is another Dimention?

 Still we do new amazing discoveries in the name of Science. UFO-sightings is nothing but some reflections in the atmosphere of some known objects or they are simply some still unexplained electric phenomena made under special weatherconditions.

 We know things today like lightning-balls, burning or glowing swampgass, phosphoricglowing microorganisms, heatreflections, sunreflections in the upper atmosphere etc. All these things are rare (heatreflections are not so rare though) and can easily confuse or even scare people unfamilliar with these things. Lightningballs for instance is only latly accepted in the physics and yet cannot be explained.

 So certainly there will be new discoveries in the future of amazing natural phenomenas. Unfortunately natural phenomenas can´t explain all UFO sightings. What about all the physical evidence like abductions, imprints, damage etc. caused by UFO´s?

 Don´t we all at times think: "There gotta be something better than this..." It could be Heaven or Eden where we all eventually will go. But maybe we don´t have to wait so long. What if a species of higher intellectallity came to Earth saving us all from ourselves and our miserable lives? That would be wonderful!

 Have we simply invented the UFO phenomenon to have something to believe in. Doesn´t it fit in better in this Space-Age? Certainly. And most people in the world have heard about UFO´s sometime in their lives whether they believe in them or not. Maybe we do not like the thought of being all alone in the universe and we hope so strong to have an evidence that there is life somewhere else that we actually imagine seing them come to us.

 There is no question that we long more and more for reaching out into space, but what if theres nothing out there to go for? Then it all would be in vain.

 This is a scary wiev and a very good reason to say that the UFO´s does not exsist at all but is only a result of our imagination and masshysteria. I don´t believe it though. How about the crowds of people having seen a UFO at the same time. Did they all misinterpretend a known phenomena, did they all excite eachother to believe in seeing an UFO? Masshypnosis? And what about the physical ecidence?