PAT Delgado, the Hampshire pioneer of research into crop circles, who helped spark global interest in the phenomenon, has died aged 90.

His best-selling book Circular Evidence, published in 1989, investigated the crop circles that appeared across the south.

Many were in fields in the Winchester area, with the Devil’s Punchbowl at Cheesefoot Head a favoured spot.

Mr Delgado, of Arle Close, Alresford, spent years researching the phenomenon alongside his friend Colin Andrews, a former electrical engineer at Test Valley Borough Council.

Mr Andrews, who now lives in the United States, paid tribute: “ Pat was a very young 90 years of age, when cancer struck and took a very rapid toll in recent weeks.

“He was a compassionate, sensitive human being, an excellent engineer and reputable healer. He was a dear friend and my co-author who was largely responsible for one of the happiest periods of my life.

“He was one of the nicest and most intelligent people I have ever met. We first met in a crop circle, of course, during 1985 and we became the best of friends.”

Fellow researcher Busty Taylor said: “Pat was a very enthusiastic person that always got stuck into a mystery and would not let go until he had an answer. I can remember him saying ‘The world loves a mystery that cannot be answered.’”

Mr Delgado had worked on the NASA Mariner project, based in Woomera, Australia in the 1960s.

He retired from active research into crop circles in 1991 after Doug Bower and Dave Chorley, from Southampton, announced that they had invented crop circles after an evening in the pub in 1976.

Mr Delgado passed away at the Royal Hampshire County Hospital on Saturday morning. (MAY23) He leaves a widow Norah.

He remained active until relatively recently, regularly playing golf at the Alresford Golf Club until his late 80s.

Factfile Crop circles started to grab attention in the late 1970s but the interest flared in the late 1980s.

They were reported around the world from Australia to the USA and Soviet Union.

Sceptics point out that all circles appear in fields with ‘tramlines’ from farm vehicles, allowing access for hoaxers.

Doug and Dave claimed to have made the circles using planks, rope, hats and wire as their only tools.

Others believe the circles can be explained by the weather; others say they are messages from extraterrestrials.

They have spawned a huge industry worth millions of pounds every year that milks the enduring public interest.

Farmers grumbled that the circles damaged their crops; but many made tidy sums out of charging the public to see them up close.