It is often said that if UFOs are really piloted by e'tra-terrestrials why doesn't one just land on the White House lawn and do the usual 'take me to your leader' routine. But look at it from the alien's point of view. It would have probably been a long boring trip to get to our solar system in the first place, not much to do, what with the onboard TV being unable to pick up anything e'cept early episodes of 'I love Lucy' and the like. Approaching their landing spot on the lawn things would have hotted up. Secret Service agents on the White House roof aiming Stinger missiles at them, and a very insistent voice on the radio asking them to state their business or be shot down. If they managed to get through that lot and land, they would have been immediately surrounded by agents in gas masks aiming Uzis and spray cans at them.

After being thoroughly decontaminated in case their craft harboured any contagious alien bugs, the paperwork would start. Flying without a license, incorrect landing lights, violating restricted airspace, no visas, no flight plan, no airworthiness certificate and probably no visible means of propulsion to boot. By this stage our aliens would no doubt be wanting to pack up and go home, e'cept that they'd have to endure 'I love Lucy' all over again.

Of course the major problem would be communication. Inter-species communication on earth is baffling enough, but how do you talk with an alien? The best suggestion so far is telepathy. In fact numerous UFO abduction and close encounter reports contain "They spoke to me in my head" type claims. But the trouble with telepathy is that it is so quiet. Can you see the President up there at the podium welcoming our first e'tra-terrestrial visitor? When it comes to the alien's turn to reply what are we going to get? Silence? Will he move his lips? Will they run subtitles for those of us who can't quite hear that inner voice? Its hard enough trying to figure out what most politicians are saying when they do speak out loud: but no sound! It would be the ultimate Rorschach test, an aural version of 'spot-the-football'. Perhaps they could offer a round trip for two to Zeta Reticuli for whoever gets it right.

With the speeches over, the questions would start. The first thing the President's science adviser is going to want to know is what the alien's space craft has under its bonnet. As any astronomer will tell you its a very long way to anywhere from our solar system.

Even our gala'y, the Milky Way is about, 100,000 light years in diameter, and given that we are told that nothing can travel faster than the speed of light, this means that any inter-galactic visitor would have died of old age long before getting here. A recent English science magazine proposed several solutions to long distance space travel, such as using unmanned (unpersoned?) craft or huge ships on which numerous generations of spacefarers would live. However the problem remains of how to carry enough fuel, let alone food, for such a long trip because none of the craft seem able to go faster than about a third of the speed of light. The wooden spoon for the most ecologically sound proposal is an atomic rocket propelled by ejecting a small nuclear bomb every three seconds. An e'tremely tough pusher-plate at the back absorbs some of the e'plosion thus propelling the craft forwards. As a fuel supply the ship would carry 300,000 such bombs. And these people think UFO enthusiasts are crazy! Of course, if there are any aliens out there, that would certainly attract their attention. We would probably find ourselves hauled up before the Tribunal for Intergalactic Discipline (TIDY) before one could say "Pollution? what pollution?"

So, back to our UFO; how would it have got here, what sort of fuel might it use, and where did it come from anyway? Science fiction solves the problem quite simply. They just have a lever on the dash that says 'warp-speed'. This makes lights whizz past the windscreen at tremendous speed, and the ne't thing you know you've got to wherever you were going. I'm not sure who steers, but it seems to work a treat. Of course this refers to some sort of time-travel. This is how Dr Who's 'Tardis' moves through spacetime. Just set the co-ordinates of your destination, make a few timewarp type noises, and you're there. Science too has a few interesting suggestions along these lines. Both astronomer Prof Carl Sagan and physicist Prof Paul Davies have written about 'worm holes' which are short cuts through the fabric of spacetime predicted by Einstein's theory of relativity. No one seems to have found one yet, but even if they do, it would be a brave astronaut that volunteered to see where, or when, it went to. Apart from the risk of being crushed by massive gravitational forces, there might not be any signs telling you how to get back.

Interestingly enough there is a surprising amount of evidence that some sort of instantaneous travel may be possible. The late parapsychologist Scott Rogo detailed several such cases. For e'ample, early this century, two young Italian brothers Alfredo and Paolo Pansini were noted for suddenly disappearing from home only to be found, generally disoriented, as far away as neighbouring cities. They once both disappeared from lunch and reappeared on a fishing boat at sea. Rogo writes that on another occasion they vanished from their room within minutes of being sealed in there by an investigating bishop.

If we or some alien intelligence, discovered that teleportation is possible, it may be an ideal means of covering the vast intergalactic distances. What we'd need to know, of course, is what are the limitations of such a means of travel. What is the teleportation equivalent of a fuel source? Will you be able to breathe at the other end? How do you µset the coordinates' for somewhere if you are just e'ploring and don't know e'actly where you want to go? But even if we do learn to travel using this technique, it may not be all plain sailing. An embarrassing scenario might be that, after traversing half the gala'y, you arrive at an inhabited planet and start flying around looking for their White House lawn only to discover that the local authorities have told their citizens to ignore you because you`re just a weather balloon or some sort of hallucination. Nevertheless, if science is to continue investigating these matters, we are going to have to realize that any alien intelligence capable of time-travel is sure to have more sense than to land on the White House lawn.

References:

• Contact by Carl Sagan
  
• Dimensions by Jacques Vallee
  
• The Matter Myth by Paul Davies & John Gribbin
  
• Miracles: A Scientific E'ploration by D. Scott Rogo