"The subject of UFOs is one of the most popular subjects for FOI requests. Answering requests takes a considerable amount of time and resources and can involve officials in days of work, which frequently means trawling through old files to find the information requested. By placing the UFO files on-line at the National Archive in a structured manner, the MoD is able to follow its remit for more open government and, by re-directing applicants to the National Archive site, reduce the amount of time it spends answering requests. By opening our files in this way, we may also help to counter the maze of rumour and frequently ill informed speculation that surrounds the role of the MoD in the UFO phenomena."

Within the next three years, everyone will be able to see the true level of interest and effectiveness demonstrated by the MoD on the topic of UFOs for themselves. This release will be a source of disappointment or vindication for some, and embarrassment for others. Conspiracy theorists who believe that the various governments of the world are hiding secrets about the 'reality' of alien visitation will see this move as another whitewash effort by the MoD and will probably continue their self-sustaining 'campaign for the truth', when the 'truth' really will be 'out there' - just that they don't believe it!

The group, which includes former military officers from seven countries, all say they have seen a UFO or have conducted research into the phenomenon.

However, the Air Force says nothing has happened in the past four decades to justify resuming investigations.

Every year thousands of people say they have seen UFOs in the United States and their claims are usually met with scepticism.

But this panel of former military, government and aviation personnel from countries around the world has urged the US government to take such claims seriously.

The group say the apparent sightings of hovering orbs, glowing lights and high-speed spacecraft are a national security concern and should no longer be dismissed.

Several pilots offered dramatic accounts of witnessing UFOs -- including a transparent flying disc and a triangular craft with mysterious markings -- as they insisted their questions needed to be taken seriously more than 30 years after the US file was closed.

"We want the US government to stop perpetuating the myth that all UFOs can be explained away in down-to-earth, conventional terms," said Fife Symington, former governor of Arizona and air force pilot who says he saw a UFO in 1997.

During his time as head of the Ministry of Defence UFO project, Nick Pope was persuaded into believing that other lifeforms may visit Earth and, more specifically, Britain.

His concern is that "highly credible" sightings are simply dismissed.

And he complains that the project he once ran is now "virtually closed" down, leaving the country "wide open" to aliens.

Mr Pope decided to speak out about his worries after resigning from his post at the Directorate of Defence Security at the MoD this week.

"The consequences of getting this one wrong could be huge," he said.

"If you reported a UFO sighting now, I am absolutely sure that you would just get back a standard letter telling you not to worry. ''Frankly we are wide open - if something does not behave like a conventional aircraft now, it will be ignored.

The files show that officials attempted to expunge information from documents released to the Public Records Office under the "30-year rule" that would have revealed the extent of the MoD's interest in UFO sightings.

In particular, the ministry wanted to cover up the operation of a secret unit dedicated to UFO investigations within the Defence Intelligence Staff. UFO conspiracy theorists have likened the unit, called DI55, to a sort of "Men in Black" agency for defending the Earth against invasion but the released documents show this is far from the truth. One 1995 memo from DI55 to the MoD's public "UFO desk" said: "I have several books at home that describe our supposed role of 'defender of the Earth against the alien menace' - it is light years from the truth!"

The files were made public following FOI requests by David Clarke, a lecturer in journalism at Sheffield Hallam University and his colleague Andy Roberts.

"These documents don't tell us anything about UFOs but they do show how desperate the MoD have been to conceal the interest which the intelligence services had in the subject," said Dr Clarke.

November 28 1980 Policeman Alan Godfrey reported seeing a six-metre wide dome-like object hovering in the air in Todmorden, West Yorkshire. He returned to the site with colleagues and they found the area where the object had supposedly been hovering was dry even though the rest of the road was wet because of earlier rain.

SK: What did you find inside Nasa?

GM: One of these people was a Nasa photographic expert, and she said that in building eight of Johnson Space Centre they regularly airbrushed out images of UFOs from the high-resolution satellite imaging. What she said was there was there: there were folders called "filtered" and "unfiltered", "processed" and "raw", something like that.

I got one picture out of the folder, and bearing in mind this is a 56k dial-up, so a very slow internet connection, in dial-up days, using the remote control programme I turned the colour down to 4bit colour and the screen resolution really, really low, and even then the picture was still juddering as it came onto the screen.

But what came on to the screen was amazing. It was a culmination of all my efforts. It was a picture of something that definitely wasn't man-made.

It was above the Earth's hemisphere. It kind of looked like a satellite. It was cigar-shaped and had geodesic domes above, below, to the left, the right and both ends of it, and although it was a low-resolution picture it was very close up.

Sounds like a pair of scenes ripped from your standard off-world fantasy novel, except the science behind these alien planets isn't fiction. Aurelia and Blue Moon are based on computer models created by NASA and SETI Project researchers to help identify which stars among the universe's 70 sextillion are most likely to support life. CGI representations of the worlds first appeared in a National Geographic documentary; the film and related interactive simulations are on display through February at the London Science Museum. A US tour is planned for this fall.

Scientists began with the essential ingredient for life: They assumed both worlds in the exhibit contained water. They then used as blueprints two scenarios formulated by the SETI Project. The first is a planet orbiting a sun close enough to keep water from freezing out, yet far enough away to avoid evaporation. The other is a moon orbiting a gas giant and warmed by twin suns.

To make the worlds as realistic as possible, SETI astrophysicist Laurance Doyle and NASA researcher Manoj Joshi ran detailed climate simulations on a desktop Linux box. The sims allowed the scientists to observe the consequences on habitability of a range of complex atmospheric variables like thermal circulation and precipitation levels. Next, a group of life scientists, led by University of Cambridge paleobiologist Simon Conway Morris, applied the principles of natural selection and adaptation to populate the planets. They determined creature leg lengths and wingspans using biomechanics algorithms, and they established vegetation height and characteristics according to factors like available light and the amount of carbon dioxide in the atmosphere.

"Implicit in these biospheres is the concept of evolution," says Conway Morris. As a result, the inhabitants of Aurelia and Blue Moon look more like something that might be encountered on the Galapagos Islands than at the cineplex. The life-forms on these pages illustrate realistic adaptations to an environment. Adaptations that almost - but not quite - befit creatures right here at home.

Saucer, toy-top, or disk-shaped "craft" without visible or audible propulsion. (day and night)

Rapidly-moving lights or lights with apparent ability to rapidly change direction — the earliest mention of their motion was given as "saucers skipping on water." Disc-shaped craft are sometimes reported to move in an irregular or "wobbly" manner at low speeds.

Large triangular "craft" or triangular light pattern

Cigar-shaped "craft" with lighted windows (Meteor fireballs are sometimes reported this way)

Another friend, Stuart Wilson, 24, managed to take video footage of the lights.

The shaky video shows a dozen pricks of light forming shapes such as diamonds, lines, characters and what looks like the Southern Cross.

The lights were visible for 10 minutes before flying in different directions and vanishing, Mr Wilson said.

"It's possible aliens are driving them, but until I see one I'm not going to be convinced," he said. "This is pretty close, but I didn't see any little green men."

But Mr Webster didn't need convincing.

"I was never into sci-fi but now I'm going to do my homework on UFOs," he said.